af_packet.c 103.1 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		PACKET - implements raw packet sockets.
 *
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 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
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 * Fixes:
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 *		Alan Cox	:	verify_area() now used correctly
 *		Alan Cox	:	new skbuff lists, look ma no backlogs!
 *		Alan Cox	:	tidied skbuff lists.
 *		Alan Cox	:	Now uses generic datagram routines I
 *					added. Also fixed the peek/read crash
 *					from all old Linux datagram code.
 *		Alan Cox	:	Uses the improved datagram code.
 *		Alan Cox	:	Added NULL's for socket options.
 *		Alan Cox	:	Re-commented the code.
 *		Alan Cox	:	Use new kernel side addressing
 *		Rob Janssen	:	Correct MTU usage.
 *		Dave Platt	:	Counter leaks caused by incorrect
 *					interrupt locking and some slightly
 *					dubious gcc output. Can you read
 *					compiler: it said _VOLATILE_
 *	Richard Kooijman	:	Timestamp fixes.
 *		Alan Cox	:	New buffers. Use sk->mac.raw.
 *		Alan Cox	:	sendmsg/recvmsg support.
 *		Alan Cox	:	Protocol setting support
 *	Alexey Kuznetsov	:	Untied from IPv4 stack.
 *	Cyrus Durgin		:	Fixed kerneld for kmod.
 *	Michal Ostrowski        :       Module initialization cleanup.
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 *         Ulises Alonso        :       Frame number limit removal and
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 *                                      packet_set_ring memory leak.
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 *		Eric Biederman	:	Allow for > 8 byte hardware addresses.
 *					The convention is that longer addresses
 *					will simply extend the hardware address
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 *					byte arrays at the end of sockaddr_ll
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 *					and packet_mreq.
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 *		Johann Baudy	:	Added TX RING.
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 *		Chetan Loke	:	Implemented TPACKET_V3 block abstraction
 *					layer.
 *					Copyright (C) 2011, <lokec@ccs.neu.edu>
 *
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 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */
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#include <linux/types.h>
#include <linux/mm.h>
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#include <linux/capability.h>
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#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
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#include <linux/kernel.h>
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#include <linux/kmod.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <net/net_namespace.h>
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#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/page.h>
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#include <asm/cacheflush.h>
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#include <asm/io.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/if_vlan.h>
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#include <linux/virtio_net.h>
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#include <linux/errqueue.h>
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#include <linux/net_tstamp.h>
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#include <linux/percpu.h>
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#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif
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#include <linux/bpf.h>
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#include "internal.h"

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/*
   Assumptions:
   - if device has no dev->hard_header routine, it adds and removes ll header
     inside itself. In this case ll header is invisible outside of device,
     but higher levels still should reserve dev->hard_header_len.
     Some devices are enough clever to reallocate skb, when header
     will not fit to reserved space (tunnel), another ones are silly
     (PPP).
   - packet socket receives packets with pulled ll header,
     so that SOCK_RAW should push it back.

On receive:
-----------

Incoming, dev->hard_header!=NULL
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   mac_header -> ll header
   data       -> data
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Outgoing, dev->hard_header!=NULL
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   mac_header -> ll header
   data       -> ll header
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Incoming, dev->hard_header==NULL
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   mac_header -> UNKNOWN position. It is very likely, that it points to ll
		 header.  PPP makes it, that is wrong, because introduce
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		 assymetry between rx and tx paths.
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   data       -> data
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Outgoing, dev->hard_header==NULL
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   mac_header -> data. ll header is still not built!
   data       -> data
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Resume
  If dev->hard_header==NULL we are unlikely to restore sensible ll header.


On transmit:
------------

dev->hard_header != NULL
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   mac_header -> ll header
   data       -> ll header
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dev->hard_header == NULL (ll header is added by device, we cannot control it)
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   mac_header -> data
   data       -> data
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   We should set nh.raw on output to correct posistion,
   packet classifier depends on it.
 */

/* Private packet socket structures. */

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/* identical to struct packet_mreq except it has
 * a longer address field.
 */
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struct packet_mreq_max {
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	int		mr_ifindex;
	unsigned short	mr_type;
	unsigned short	mr_alen;
	unsigned char	mr_address[MAX_ADDR_LEN];
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};
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union tpacket_uhdr {
	struct tpacket_hdr  *h1;
	struct tpacket2_hdr *h2;
	struct tpacket3_hdr *h3;
	void *raw;
};

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static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
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		int closing, int tx_ring);

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#define V3_ALIGNMENT	(8)

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#define BLK_HDR_LEN	(ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
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#define BLK_PLUS_PRIV(sz_of_priv) \
	(BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))

#define PGV_FROM_VMALLOC 1
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#define BLOCK_STATUS(x)	((x)->hdr.bh1.block_status)
#define BLOCK_NUM_PKTS(x)	((x)->hdr.bh1.num_pkts)
#define BLOCK_O2FP(x)		((x)->hdr.bh1.offset_to_first_pkt)
#define BLOCK_LEN(x)		((x)->hdr.bh1.blk_len)
#define BLOCK_SNUM(x)		((x)->hdr.bh1.seq_num)
#define BLOCK_O2PRIV(x)	((x)->offset_to_priv)
#define BLOCK_PRIV(x)		((void *)((char *)(x) + BLOCK_O2PRIV(x)))

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struct packet_sock;
static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
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static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
		       struct packet_type *pt, struct net_device *orig_dev);
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static void *packet_previous_frame(struct packet_sock *po,
		struct packet_ring_buffer *rb,
		int status);
static void packet_increment_head(struct packet_ring_buffer *buff);
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static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
			struct tpacket_block_desc *);
static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
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			struct packet_sock *);
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static void prb_retire_current_block(struct tpacket_kbdq_core *,
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		struct packet_sock *, unsigned int status);
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static int prb_queue_frozen(struct tpacket_kbdq_core *);
static void prb_open_block(struct tpacket_kbdq_core *,
		struct tpacket_block_desc *);
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static void prb_retire_rx_blk_timer_expired(unsigned long);
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static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
static void prb_init_blk_timer(struct packet_sock *,
		struct tpacket_kbdq_core *,
		void (*func) (unsigned long));
static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
static void prb_clear_rxhash(struct tpacket_kbdq_core *,
		struct tpacket3_hdr *);
static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
		struct tpacket3_hdr *);
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static void packet_flush_mclist(struct sock *sk);

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struct packet_skb_cb {
	union {
		struct sockaddr_pkt pkt;
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		union {
			/* Trick: alias skb original length with
			 * ll.sll_family and ll.protocol in order
			 * to save room.
			 */
			unsigned int origlen;
			struct sockaddr_ll ll;
		};
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	} sa;
};

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#define vio_le() virtio_legacy_is_little_endian()

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#define PACKET_SKB_CB(__skb)	((struct packet_skb_cb *)((__skb)->cb))
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#define GET_PBDQC_FROM_RB(x)	((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
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#define GET_PBLOCK_DESC(x, bid)	\
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	((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
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#define GET_CURR_PBLOCK_DESC_FROM_CORE(x)	\
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	((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
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#define GET_NEXT_PRB_BLK_NUM(x) \
	(((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
	((x)->kactive_blk_num+1) : 0)

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static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
static void __fanout_link(struct sock *sk, struct packet_sock *po);

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static int packet_direct_xmit(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
	netdev_features_t features;
	struct netdev_queue *txq;
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	int ret = NETDEV_TX_BUSY;
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	if (unlikely(!netif_running(dev) ||
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		     !netif_carrier_ok(dev)))
		goto drop;
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	features = netif_skb_features(skb);
	if (skb_needs_linearize(skb, features) &&
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	    __skb_linearize(skb))
		goto drop;
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	txq = skb_get_tx_queue(dev, skb);
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	local_bh_disable();

	HARD_TX_LOCK(dev, txq, smp_processor_id());
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	if (!netif_xmit_frozen_or_drv_stopped(txq))
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		ret = netdev_start_xmit(skb, dev, txq, false);
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	HARD_TX_UNLOCK(dev, txq);
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	local_bh_enable();

	if (!dev_xmit_complete(ret))
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		kfree_skb(skb);
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	return ret;
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drop:
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	atomic_long_inc(&dev->tx_dropped);
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	kfree_skb(skb);
	return NET_XMIT_DROP;
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}

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static struct net_device *packet_cached_dev_get(struct packet_sock *po)
{
	struct net_device *dev;

	rcu_read_lock();
	dev = rcu_dereference(po->cached_dev);
	if (likely(dev))
		dev_hold(dev);
	rcu_read_unlock();

	return dev;
}

static void packet_cached_dev_assign(struct packet_sock *po,
				     struct net_device *dev)
{
	rcu_assign_pointer(po->cached_dev, dev);
}

static void packet_cached_dev_reset(struct packet_sock *po)
{
	RCU_INIT_POINTER(po->cached_dev, NULL);
}

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static bool packet_use_direct_xmit(const struct packet_sock *po)
{
	return po->xmit == packet_direct_xmit;
}

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static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
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{
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	return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
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}

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static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	u16 queue_index;

	if (ops->ndo_select_queue) {
		queue_index = ops->ndo_select_queue(dev, skb, NULL,
						    __packet_pick_tx_queue);
		queue_index = netdev_cap_txqueue(dev, queue_index);
	} else {
		queue_index = __packet_pick_tx_queue(dev, skb);
	}

	skb_set_queue_mapping(skb, queue_index);
}

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/* register_prot_hook must be invoked with the po->bind_lock held,
 * or from a context in which asynchronous accesses to the packet
 * socket is not possible (packet_create()).
 */
static void register_prot_hook(struct sock *sk)
{
	struct packet_sock *po = pkt_sk(sk);
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	if (!po->running) {
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		if (po->fanout)
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			__fanout_link(sk, po);
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		else
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			dev_add_pack(&po->prot_hook);
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		sock_hold(sk);
		po->running = 1;
	}
}

/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
 * held.   If the sync parameter is true, we will temporarily drop
 * the po->bind_lock and do a synchronize_net to make sure no
 * asynchronous packet processing paths still refer to the elements
 * of po->prot_hook.  If the sync parameter is false, it is the
 * callers responsibility to take care of this.
 */
static void __unregister_prot_hook(struct sock *sk, bool sync)
{
	struct packet_sock *po = pkt_sk(sk);

	po->running = 0;
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	if (po->fanout)
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		__fanout_unlink(sk, po);
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	else
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		__dev_remove_pack(&po->prot_hook);
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	__sock_put(sk);

	if (sync) {
		spin_unlock(&po->bind_lock);
		synchronize_net();
		spin_lock(&po->bind_lock);
	}
}

static void unregister_prot_hook(struct sock *sk, bool sync)
{
	struct packet_sock *po = pkt_sk(sk);

	if (po->running)
		__unregister_prot_hook(sk, sync);
}

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static inline struct page * __pure pgv_to_page(void *addr)
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{
	if (is_vmalloc_addr(addr))
		return vmalloc_to_page(addr);
	return virt_to_page(addr);
}

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static void __packet_set_status(struct packet_sock *po, void *frame, int status)
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{
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	union tpacket_uhdr h;
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	h.raw = frame;
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	switch (po->tp_version) {
	case TPACKET_V1:
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		h.h1->tp_status = status;
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		flush_dcache_page(pgv_to_page(&h.h1->tp_status));
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		break;
	case TPACKET_V2:
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		h.h2->tp_status = status;
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		flush_dcache_page(pgv_to_page(&h.h2->tp_status));
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		break;
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	case TPACKET_V3:
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	default:
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		WARN(1, "TPACKET version not supported.\n");
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		BUG();
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	}
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	smp_wmb();
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}

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static int __packet_get_status(struct packet_sock *po, void *frame)
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{
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	union tpacket_uhdr h;
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	smp_rmb();

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	h.raw = frame;
	switch (po->tp_version) {
	case TPACKET_V1:
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		flush_dcache_page(pgv_to_page(&h.h1->tp_status));
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		return h.h1->tp_status;
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	case TPACKET_V2:
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		flush_dcache_page(pgv_to_page(&h.h2->tp_status));
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		return h.h2->tp_status;
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	case TPACKET_V3:
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	default:
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		WARN(1, "TPACKET version not supported.\n");
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		BUG();
		return 0;
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	}
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}
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static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
				   unsigned int flags)
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{
	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);

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	if (shhwtstamps &&
	    (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
	    ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
		return TP_STATUS_TS_RAW_HARDWARE;
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	if (ktime_to_timespec_cond(skb->tstamp, ts))
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		return TP_STATUS_TS_SOFTWARE;
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	return 0;
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}

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static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
				    struct sk_buff *skb)
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{
	union tpacket_uhdr h;
	struct timespec ts;
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	__u32 ts_status;
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	if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
		return 0;
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	h.raw = frame;
	switch (po->tp_version) {
	case TPACKET_V1:
		h.h1->tp_sec = ts.tv_sec;
		h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
		break;
	case TPACKET_V2:
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
		break;
	case TPACKET_V3:
	default:
		WARN(1, "TPACKET version not supported.\n");
		BUG();
	}

	/* one flush is safe, as both fields always lie on the same cacheline */
	flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
	smp_wmb();
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	return ts_status;
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}

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static void *packet_lookup_frame(struct packet_sock *po,
		struct packet_ring_buffer *rb,
		unsigned int position,
		int status)
{
	unsigned int pg_vec_pos, frame_offset;
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	union tpacket_uhdr h;
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	pg_vec_pos = position / rb->frames_per_block;
	frame_offset = position % rb->frames_per_block;

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	h.raw = rb->pg_vec[pg_vec_pos].buffer +
		(frame_offset * rb->frame_size);
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	if (status != __packet_get_status(po, h.raw))
		return NULL;

	return h.raw;
}

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static void *packet_current_frame(struct packet_sock *po,
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		struct packet_ring_buffer *rb,
		int status)
{
	return packet_lookup_frame(po, rb, rb->head, status);
}

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static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
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{
	del_timer_sync(&pkc->retire_blk_timer);
}

static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
		struct sk_buff_head *rb_queue)
{
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	struct tpacket_kbdq_core *pkc;
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	pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
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	spin_lock_bh(&rb_queue->lock);
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	pkc->delete_blk_timer = 1;
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	spin_unlock_bh(&rb_queue->lock);
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	prb_del_retire_blk_timer(pkc);
}

static void prb_init_blk_timer(struct packet_sock *po,
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		struct tpacket_kbdq_core *pkc,
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		void (*func) (unsigned long))
{
	init_timer(&pkc->retire_blk_timer);
	pkc->retire_blk_timer.data = (long)po;
	pkc->retire_blk_timer.function = func;
	pkc->retire_blk_timer.expires = jiffies;
}

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static void prb_setup_retire_blk_timer(struct packet_sock *po)
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{
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	struct tpacket_kbdq_core *pkc;
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	pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
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	prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
}

static int prb_calc_retire_blk_tmo(struct packet_sock *po,
				int blk_size_in_bytes)
{
	struct net_device *dev;
	unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
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	struct ethtool_cmd ecmd;
	int err;
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	u32 speed;
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	rtnl_lock();
	dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
	if (unlikely(!dev)) {
		rtnl_unlock();
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		return DEFAULT_PRB_RETIRE_TOV;
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	}
	err = __ethtool_get_settings(dev, &ecmd);
571
	speed = ethtool_cmd_speed(&ecmd);
572 573 574 575 576 577
	rtnl_unlock();
	if (!err) {
		/*
		 * If the link speed is so slow you don't really
		 * need to worry about perf anyways
		 */
578
		if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
579
			return DEFAULT_PRB_RETIRE_TOV;
580 581 582
		} else {
			msec = 1;
			div = speed / 1000;
583 584 585 586 587 588 589 590 591 592 593 594 595 596 597
		}
	}

	mbits = (blk_size_in_bytes * 8) / (1024 * 1024);

	if (div)
		mbits /= div;

	tmo = mbits * msec;

	if (div)
		return tmo+1;
	return tmo;
}

598
static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
599 600 601 602 603 604 605 606
			union tpacket_req_u *req_u)
{
	p1->feature_req_word = req_u->req3.tp_feature_req_word;
}

static void init_prb_bdqc(struct packet_sock *po,
			struct packet_ring_buffer *rb,
			struct pgv *pg_vec,
607
			union tpacket_req_u *req_u)
608
{
609
	struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
610
	struct tpacket_block_desc *pbd;
611 612 613 614 615

	memset(p1, 0x0, sizeof(*p1));

	p1->knxt_seq_num = 1;
	p1->pkbdq = pg_vec;
616
	pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
J
Joe Perches 已提交
617
	p1->pkblk_start	= pg_vec[0].buffer;
618 619 620 621 622
	p1->kblk_size = req_u->req3.tp_block_size;
	p1->knum_blocks	= req_u->req3.tp_block_nr;
	p1->hdrlen = po->tp_hdrlen;
	p1->version = po->tp_version;
	p1->last_kactive_blk_num = 0;
623
	po->stats.stats3.tp_freeze_q_cnt = 0;
624 625 626 627 628 629 630 631
	if (req_u->req3.tp_retire_blk_tov)
		p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
	else
		p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
						req_u->req3.tp_block_size);
	p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
	p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;

632
	p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
633
	prb_init_ft_ops(p1, req_u);
634
	prb_setup_retire_blk_timer(po);
635 636 637 638 639 640
	prb_open_block(p1, pbd);
}

/*  Do NOT update the last_blk_num first.
 *  Assumes sk_buff_head lock is held.
 */
641
static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673
{
	mod_timer(&pkc->retire_blk_timer,
			jiffies + pkc->tov_in_jiffies);
	pkc->last_kactive_blk_num = pkc->kactive_blk_num;
}

/*
 * Timer logic:
 * 1) We refresh the timer only when we open a block.
 *    By doing this we don't waste cycles refreshing the timer
 *	  on packet-by-packet basis.
 *
 * With a 1MB block-size, on a 1Gbps line, it will take
 * i) ~8 ms to fill a block + ii) memcpy etc.
 * In this cut we are not accounting for the memcpy time.
 *
 * So, if the user sets the 'tmo' to 10ms then the timer
 * will never fire while the block is still getting filled
 * (which is what we want). However, the user could choose
 * to close a block early and that's fine.
 *
 * But when the timer does fire, we check whether or not to refresh it.
 * Since the tmo granularity is in msecs, it is not too expensive
 * to refresh the timer, lets say every '8' msecs.
 * Either the user can set the 'tmo' or we can derive it based on
 * a) line-speed and b) block-size.
 * prb_calc_retire_blk_tmo() calculates the tmo.
 *
 */
static void prb_retire_rx_blk_timer_expired(unsigned long data)
{
	struct packet_sock *po = (struct packet_sock *)data;
674
	struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
675
	unsigned int frozen;
676
	struct tpacket_block_desc *pbd;
677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703

	spin_lock(&po->sk.sk_receive_queue.lock);

	frozen = prb_queue_frozen(pkc);
	pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);

	if (unlikely(pkc->delete_blk_timer))
		goto out;

	/* We only need to plug the race when the block is partially filled.
	 * tpacket_rcv:
	 *		lock(); increment BLOCK_NUM_PKTS; unlock()
	 *		copy_bits() is in progress ...
	 *		timer fires on other cpu:
	 *		we can't retire the current block because copy_bits
	 *		is in progress.
	 *
	 */
	if (BLOCK_NUM_PKTS(pbd)) {
		while (atomic_read(&pkc->blk_fill_in_prog)) {
			/* Waiting for skb_copy_bits to finish... */
			cpu_relax();
		}
	}

	if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
		if (!frozen) {
704 705 706 707
			if (!BLOCK_NUM_PKTS(pbd)) {
				/* An empty block. Just refresh the timer. */
				goto refresh_timer;
			}
708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743
			prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
			if (!prb_dispatch_next_block(pkc, po))
				goto refresh_timer;
			else
				goto out;
		} else {
			/* Case 1. Queue was frozen because user-space was
			 *	   lagging behind.
			 */
			if (prb_curr_blk_in_use(pkc, pbd)) {
				/*
				 * Ok, user-space is still behind.
				 * So just refresh the timer.
				 */
				goto refresh_timer;
			} else {
			       /* Case 2. queue was frozen,user-space caught up,
				* now the link went idle && the timer fired.
				* We don't have a block to close.So we open this
				* block and restart the timer.
				* opening a block thaws the queue,restarts timer
				* Thawing/timer-refresh is a side effect.
				*/
				prb_open_block(pkc, pbd);
				goto out;
			}
		}
	}

refresh_timer:
	_prb_refresh_rx_retire_blk_timer(pkc);

out:
	spin_unlock(&po->sk.sk_receive_queue.lock);
}

744
static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
745
		struct tpacket_block_desc *pbd1, __u32 status)
746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786
{
	/* Flush everything minus the block header */

#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
	u8 *start, *end;

	start = (u8 *)pbd1;

	/* Skip the block header(we know header WILL fit in 4K) */
	start += PAGE_SIZE;

	end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
	for (; start < end; start += PAGE_SIZE)
		flush_dcache_page(pgv_to_page(start));

	smp_wmb();
#endif

	/* Now update the block status. */

	BLOCK_STATUS(pbd1) = status;

	/* Flush the block header */

#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
	start = (u8 *)pbd1;
	flush_dcache_page(pgv_to_page(start));

	smp_wmb();
#endif
}

/*
 * Side effect:
 *
 * 1) flush the block
 * 2) Increment active_blk_num
 *
 * Note:We DONT refresh the timer on purpose.
 *	Because almost always the next block will be opened.
 */
787 788
static void prb_close_block(struct tpacket_kbdq_core *pkc1,
		struct tpacket_block_desc *pbd1,
789 790 791 792 793
		struct packet_sock *po, unsigned int stat)
{
	__u32 status = TP_STATUS_USER | stat;

	struct tpacket3_hdr *last_pkt;
794
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
795
	struct sock *sk = &po->sk;
796

797
	if (po->stats.stats3.tp_drops)
798 799 800 801 802 803 804 805 806 807
		status |= TP_STATUS_LOSING;

	last_pkt = (struct tpacket3_hdr *)pkc1->prev;
	last_pkt->tp_next_offset = 0;

	/* Get the ts of the last pkt */
	if (BLOCK_NUM_PKTS(pbd1)) {
		h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
		h1->ts_last_pkt.ts_nsec	= last_pkt->tp_nsec;
	} else {
808 809 810 811 812
		/* Ok, we tmo'd - so get the current time.
		 *
		 * It shouldn't really happen as we don't close empty
		 * blocks. See prb_retire_rx_blk_timer_expired().
		 */
813 814 815 816 817 818 819 820 821 822 823
		struct timespec ts;
		getnstimeofday(&ts);
		h1->ts_last_pkt.ts_sec = ts.tv_sec;
		h1->ts_last_pkt.ts_nsec	= ts.tv_nsec;
	}

	smp_wmb();

	/* Flush the block */
	prb_flush_block(pkc1, pbd1, status);

824 825
	sk->sk_data_ready(sk);

826 827 828
	pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
}

829
static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
830 831 832 833 834 835 836 837 838 839 840
{
	pkc->reset_pending_on_curr_blk = 0;
}

/*
 * Side effect of opening a block:
 *
 * 1) prb_queue is thawed.
 * 2) retire_blk_timer is refreshed.
 *
 */
841 842
static void prb_open_block(struct tpacket_kbdq_core *pkc1,
	struct tpacket_block_desc *pbd1)
843 844
{
	struct timespec ts;
845
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
846 847 848

	smp_rmb();

849 850 851
	/* We could have just memset this but we will lose the
	 * flexibility of making the priv area sticky
	 */
852

853 854 855
	BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
	BLOCK_NUM_PKTS(pbd1) = 0;
	BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
856

857 858 859 860
	getnstimeofday(&ts);

	h1->ts_first_pkt.ts_sec = ts.tv_sec;
	h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
861

862 863 864 865 866 867 868 869 870 871 872 873 874 875
	pkc1->pkblk_start = (char *)pbd1;
	pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);

	BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
	BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;

	pbd1->version = pkc1->version;
	pkc1->prev = pkc1->nxt_offset;
	pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;

	prb_thaw_queue(pkc1);
	_prb_refresh_rx_retire_blk_timer(pkc1);

	smp_wmb();
876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900
}

/*
 * Queue freeze logic:
 * 1) Assume tp_block_nr = 8 blocks.
 * 2) At time 't0', user opens Rx ring.
 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
 * 4) user-space is either sleeping or processing block '0'.
 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
 *    it will close block-7,loop around and try to fill block '0'.
 *    call-flow:
 *    __packet_lookup_frame_in_block
 *      prb_retire_current_block()
 *      prb_dispatch_next_block()
 *        |->(BLOCK_STATUS == USER) evaluates to true
 *    5.1) Since block-0 is currently in-use, we just freeze the queue.
 * 6) Now there are two cases:
 *    6.1) Link goes idle right after the queue is frozen.
 *         But remember, the last open_block() refreshed the timer.
 *         When this timer expires,it will refresh itself so that we can
 *         re-open block-0 in near future.
 *    6.2) Link is busy and keeps on receiving packets. This is a simple
 *         case and __packet_lookup_frame_in_block will check if block-0
 *         is free and can now be re-used.
 */
901
static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
902 903 904
				  struct packet_sock *po)
{
	pkc->reset_pending_on_curr_blk = 1;
905
	po->stats.stats3.tp_freeze_q_cnt++;
906 907 908 909 910 911 912 913 914 915
}

#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))

/*
 * If the next block is free then we will dispatch it
 * and return a good offset.
 * Else, we will freeze the queue.
 * So, caller must check the return value.
 */
916
static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
917 918
		struct packet_sock *po)
{
919
	struct tpacket_block_desc *pbd;
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940

	smp_rmb();

	/* 1. Get current block num */
	pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);

	/* 2. If this block is currently in_use then freeze the queue */
	if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
		prb_freeze_queue(pkc, po);
		return NULL;
	}

	/*
	 * 3.
	 * open this block and return the offset where the first packet
	 * needs to get stored.
	 */
	prb_open_block(pkc, pbd);
	return (void *)pkc->nxt_offset;
}

941
static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
942 943
		struct packet_sock *po, unsigned int status)
{
944
	struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967

	/* retire/close the current block */
	if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
		/*
		 * Plug the case where copy_bits() is in progress on
		 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
		 * have space to copy the pkt in the current block and
		 * called prb_retire_current_block()
		 *
		 * We don't need to worry about the TMO case because
		 * the timer-handler already handled this case.
		 */
		if (!(status & TP_STATUS_BLK_TMO)) {
			while (atomic_read(&pkc->blk_fill_in_prog)) {
				/* Waiting for skb_copy_bits to finish... */
				cpu_relax();
			}
		}
		prb_close_block(pkc, pbd, po, status);
		return;
	}
}

968
static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
969
				      struct tpacket_block_desc *pbd)
970 971 972 973
{
	return TP_STATUS_USER & BLOCK_STATUS(pbd);
}

974
static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
975 976 977 978
{
	return pkc->reset_pending_on_curr_blk;
}

979
static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
980
{
981
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
982 983 984
	atomic_dec(&pkc->blk_fill_in_prog);
}

985
static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
986 987
			struct tpacket3_hdr *ppd)
{
988
	ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
989 990
}

991
static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
992 993 994 995 996
			struct tpacket3_hdr *ppd)
{
	ppd->hv1.tp_rxhash = 0;
}

997
static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
998 999
			struct tpacket3_hdr *ppd)
{
1000 1001
	if (skb_vlan_tag_present(pkc->skb)) {
		ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1002 1003
		ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
		ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1004
	} else {
1005
		ppd->hv1.tp_vlan_tci = 0;
1006
		ppd->hv1.tp_vlan_tpid = 0;
1007
		ppd->tp_status = TP_STATUS_AVAILABLE;
1008 1009 1010
	}
}

1011
static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1012 1013
			struct tpacket3_hdr *ppd)
{
1014
	ppd->hv1.tp_padding = 0;
1015 1016 1017 1018 1019 1020 1021 1022
	prb_fill_vlan_info(pkc, ppd);

	if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
		prb_fill_rxhash(pkc, ppd);
	else
		prb_clear_rxhash(pkc, ppd);
}

1023
static void prb_fill_curr_block(char *curr,
1024 1025
				struct tpacket_kbdq_core *pkc,
				struct tpacket_block_desc *pbd,
1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046
				unsigned int len)
{
	struct tpacket3_hdr *ppd;

	ppd  = (struct tpacket3_hdr *)curr;
	ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
	pkc->prev = curr;
	pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
	BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
	BLOCK_NUM_PKTS(pbd) += 1;
	atomic_inc(&pkc->blk_fill_in_prog);
	prb_run_all_ft_ops(pkc, ppd);
}

/* Assumes caller has the sk->rx_queue.lock */
static void *__packet_lookup_frame_in_block(struct packet_sock *po,
					    struct sk_buff *skb,
						int status,
					    unsigned int len
					    )
{
1047 1048
	struct tpacket_kbdq_core *pkc;
	struct tpacket_block_desc *pbd;
1049 1050
	char *curr, *end;

J
Joe Perches 已提交
1051
	pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076
	pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);

	/* Queue is frozen when user space is lagging behind */
	if (prb_queue_frozen(pkc)) {
		/*
		 * Check if that last block which caused the queue to freeze,
		 * is still in_use by user-space.
		 */
		if (prb_curr_blk_in_use(pkc, pbd)) {
			/* Can't record this packet */
			return NULL;
		} else {
			/*
			 * Ok, the block was released by user-space.
			 * Now let's open that block.
			 * opening a block also thaws the queue.
			 * Thawing is a side effect.
			 */
			prb_open_block(pkc, pbd);
		}
	}

	smp_mb();
	curr = pkc->nxt_offset;
	pkc->skb = skb;
J
Joe Perches 已提交
1077
	end = (char *)pbd + pkc->kblk_size;
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102

	/* first try the current block */
	if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
		prb_fill_curr_block(curr, pkc, pbd, len);
		return (void *)curr;
	}

	/* Ok, close the current block */
	prb_retire_current_block(pkc, po, 0);

	/* Now, try to dispatch the next block */
	curr = (char *)prb_dispatch_next_block(pkc, po);
	if (curr) {
		pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
		prb_fill_curr_block(curr, pkc, pbd, len);
		return (void *)curr;
	}

	/*
	 * No free blocks are available.user_space hasn't caught up yet.
	 * Queue was just frozen and now this packet will get dropped.
	 */
	return NULL;
}

1103
static void *packet_current_rx_frame(struct packet_sock *po,
1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118
					    struct sk_buff *skb,
					    int status, unsigned int len)
{
	char *curr = NULL;
	switch (po->tp_version) {
	case TPACKET_V1:
	case TPACKET_V2:
		curr = packet_lookup_frame(po, &po->rx_ring,
					po->rx_ring.head, status);
		return curr;
	case TPACKET_V3:
		return __packet_lookup_frame_in_block(po, skb, status, len);
	default:
		WARN(1, "TPACKET version not supported\n");
		BUG();
1119
		return NULL;
1120 1121 1122
	}
}

1123
static void *prb_lookup_block(struct packet_sock *po,
1124
				     struct packet_ring_buffer *rb,
1125
				     unsigned int idx,
1126 1127
				     int status)
{
1128
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1129
	struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1130 1131 1132 1133 1134 1135

	if (status != BLOCK_STATUS(pbd))
		return NULL;
	return pbd;
}

1136
static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1137 1138 1139 1140 1141 1142 1143 1144 1145 1146
{
	unsigned int prev;
	if (rb->prb_bdqc.kactive_blk_num)
		prev = rb->prb_bdqc.kactive_blk_num-1;
	else
		prev = rb->prb_bdqc.knum_blocks-1;
	return prev;
}

/* Assumes caller has held the rx_queue.lock */
1147
static void *__prb_previous_block(struct packet_sock *po,
1148 1149 1150 1151 1152 1153 1154
					 struct packet_ring_buffer *rb,
					 int status)
{
	unsigned int previous = prb_previous_blk_num(rb);
	return prb_lookup_block(po, rb, previous, status);
}

1155
static void *packet_previous_rx_frame(struct packet_sock *po,
1156 1157 1158 1159 1160 1161 1162 1163 1164
					     struct packet_ring_buffer *rb,
					     int status)
{
	if (po->tp_version <= TPACKET_V2)
		return packet_previous_frame(po, rb, status);

	return __prb_previous_block(po, rb, status);
}

1165
static void packet_increment_rx_head(struct packet_sock *po,
1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179
					    struct packet_ring_buffer *rb)
{
	switch (po->tp_version) {
	case TPACKET_V1:
	case TPACKET_V2:
		return packet_increment_head(rb);
	case TPACKET_V3:
	default:
		WARN(1, "TPACKET version not supported.\n");
		BUG();
		return;
	}
}

1180
static void *packet_previous_frame(struct packet_sock *po,
J
Johann Baudy 已提交
1181 1182 1183 1184 1185 1186 1187
		struct packet_ring_buffer *rb,
		int status)
{
	unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
	return packet_lookup_frame(po, rb, previous, status);
}

1188
static void packet_increment_head(struct packet_ring_buffer *buff)
J
Johann Baudy 已提交
1189 1190 1191 1192
{
	buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}

1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233
static void packet_inc_pending(struct packet_ring_buffer *rb)
{
	this_cpu_inc(*rb->pending_refcnt);
}

static void packet_dec_pending(struct packet_ring_buffer *rb)
{
	this_cpu_dec(*rb->pending_refcnt);
}

static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
{
	unsigned int refcnt = 0;
	int cpu;

	/* We don't use pending refcount in rx_ring. */
	if (rb->pending_refcnt == NULL)
		return 0;

	for_each_possible_cpu(cpu)
		refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);

	return refcnt;
}

static int packet_alloc_pending(struct packet_sock *po)
{
	po->rx_ring.pending_refcnt = NULL;

	po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
	if (unlikely(po->tx_ring.pending_refcnt == NULL))
		return -ENOBUFS;

	return 0;
}

static void packet_free_pending(struct packet_sock *po)
{
	free_percpu(po->tx_ring.pending_refcnt);
}

1234 1235 1236 1237 1238 1239
#define ROOM_POW_OFF	2
#define ROOM_NONE	0x0
#define ROOM_LOW	0x1
#define ROOM_NORMAL	0x2

static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1240
{
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
	int idx, len;

	len = po->rx_ring.frame_max + 1;
	idx = po->rx_ring.head;
	if (pow_off)
		idx += len >> pow_off;
	if (idx >= len)
		idx -= len;
	return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
}

static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
{
	int idx, len;

	len = po->rx_ring.prb_bdqc.knum_blocks;
	idx = po->rx_ring.prb_bdqc.kactive_blk_num;
	if (pow_off)
		idx += len >> pow_off;
	if (idx >= len)
		idx -= len;
	return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
}
1264

1265
static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1266 1267 1268 1269 1270 1271
{
	struct sock *sk = &po->sk;
	int ret = ROOM_NONE;

	if (po->prot_hook.func != tpacket_rcv) {
		int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1272
					  - (skb ? skb->truesize : 0);
1273 1274 1275 1276 1277 1278 1279
		if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
			return ROOM_NORMAL;
		else if (avail > 0)
			return ROOM_LOW;
		else
			return ROOM_NONE;
	}
1280

1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291
	if (po->tp_version == TPACKET_V3) {
		if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
			ret = ROOM_NORMAL;
		else if (__tpacket_v3_has_room(po, 0))
			ret = ROOM_LOW;
	} else {
		if (__tpacket_has_room(po, ROOM_POW_OFF))
			ret = ROOM_NORMAL;
		else if (__tpacket_has_room(po, 0))
			ret = ROOM_LOW;
	}
1292 1293 1294 1295 1296 1297 1298 1299 1300

	return ret;
}

static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
{
	int ret;
	bool has_room;

1301 1302
	spin_lock_bh(&po->sk.sk_receive_queue.lock);
	ret = __packet_rcv_has_room(po, skb);
1303 1304
	has_room = ret == ROOM_NORMAL;
	if (po->pressure == has_room)
1305 1306
		po->pressure = !has_room;
	spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1307

1308
	return ret;
1309 1310
}

L
Linus Torvalds 已提交
1311 1312
static void packet_sock_destruct(struct sock *sk)
{
1313 1314
	skb_queue_purge(&sk->sk_error_queue);

1315 1316
	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
L
Linus Torvalds 已提交
1317 1318

	if (!sock_flag(sk, SOCK_DEAD)) {
E
Eric Dumazet 已提交
1319
		pr_err("Attempt to release alive packet socket: %p\n", sk);
L
Linus Torvalds 已提交
1320 1321 1322
		return;
	}

1323
	sk_refcnt_debug_dec(sk);
L
Linus Torvalds 已提交
1324 1325
}

1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339
static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
{
	u32 rxhash;
	int i, count = 0;

	rxhash = skb_get_hash(skb);
	for (i = 0; i < ROLLOVER_HLEN; i++)
		if (po->rollover->history[i] == rxhash)
			count++;

	po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash;
	return count > (ROLLOVER_HLEN >> 1);
}

1340 1341 1342
static unsigned int fanout_demux_hash(struct packet_fanout *f,
				      struct sk_buff *skb,
				      unsigned int num)
D
David S. Miller 已提交
1343
{
1344
	return reciprocal_scale(skb_get_hash(skb), num);
D
David S. Miller 已提交
1345 1346
}

1347 1348 1349
static unsigned int fanout_demux_lb(struct packet_fanout *f,
				    struct sk_buff *skb,
				    unsigned int num)
D
David S. Miller 已提交
1350
{
1351
	unsigned int val = atomic_inc_return(&f->rr_cur);
D
David S. Miller 已提交
1352

1353
	return val % num;
1354 1355 1356 1357 1358 1359 1360
}

static unsigned int fanout_demux_cpu(struct packet_fanout *f,
				     struct sk_buff *skb,
				     unsigned int num)
{
	return smp_processor_id() % num;
D
David S. Miller 已提交
1361 1362
}

1363 1364 1365 1366
static unsigned int fanout_demux_rnd(struct packet_fanout *f,
				     struct sk_buff *skb,
				     unsigned int num)
{
1367
	return prandom_u32_max(num);
1368 1369
}

1370 1371
static unsigned int fanout_demux_rollover(struct packet_fanout *f,
					  struct sk_buff *skb,
1372
					  unsigned int idx, bool try_self,
1373
					  unsigned int num)
1374
{
1375
	struct packet_sock *po, *po_next, *po_skip = NULL;
W
Willem de Bruijn 已提交
1376
	unsigned int i, j, room = ROOM_NONE;
1377

1378
	po = pkt_sk(f->arr[idx]);
1379 1380 1381 1382 1383 1384

	if (try_self) {
		room = packet_rcv_has_room(po, skb);
		if (room == ROOM_NORMAL ||
		    (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
			return idx;
1385
		po_skip = po;
1386
	}
1387

1388
	i = j = min_t(int, po->rollover->sock, num - 1);
1389
	do {
1390
		po_next = pkt_sk(f->arr[i]);
1391
		if (po_next != po_skip && !po_next->pressure &&
1392
		    packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1393
			if (i != j)
1394
				po->rollover->sock = i;
W
Willem de Bruijn 已提交
1395 1396 1397
			atomic_long_inc(&po->rollover->num);
			if (room == ROOM_LOW)
				atomic_long_inc(&po->rollover->num_huge);
1398 1399
			return i;
		}
1400

1401 1402 1403 1404
		if (++i == num)
			i = 0;
	} while (i != j);

W
Willem de Bruijn 已提交
1405
	atomic_long_inc(&po->rollover->num_failed);
1406 1407 1408
	return idx;
}

1409 1410 1411 1412 1413 1414 1415
static unsigned int fanout_demux_qm(struct packet_fanout *f,
				    struct sk_buff *skb,
				    unsigned int num)
{
	return skb_get_queue_mapping(skb) % num;
}

1416 1417 1418 1419 1420 1421 1422 1423 1424 1425
static unsigned int fanout_demux_bpf(struct packet_fanout *f,
				     struct sk_buff *skb,
				     unsigned int num)
{
	struct bpf_prog *prog;
	unsigned int ret = 0;

	rcu_read_lock();
	prog = rcu_dereference(f->bpf_prog);
	if (prog)
1426
		ret = bpf_prog_run_clear_cb(prog, skb) % num;
1427 1428 1429 1430 1431
	rcu_read_unlock();

	return ret;
}

1432 1433 1434
static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
{
	return f->flags & (flag >> 8);
1435 1436 1437 1438
}

static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
			     struct packet_type *pt, struct net_device *orig_dev)
D
David S. Miller 已提交
1439 1440
{
	struct packet_fanout *f = pt->af_packet_priv;
1441
	unsigned int num = READ_ONCE(f->num_members);
D
David S. Miller 已提交
1442
	struct packet_sock *po;
1443
	unsigned int idx;
D
David S. Miller 已提交
1444 1445 1446 1447 1448 1449 1450

	if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
	    !num) {
		kfree_skb(skb);
		return 0;
	}

1451 1452 1453 1454 1455
	if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
		skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
		if (!skb)
			return 0;
	}
1456 1457 1458
	switch (f->type) {
	case PACKET_FANOUT_HASH:
	default:
1459
		idx = fanout_demux_hash(f, skb, num);
1460 1461
		break;
	case PACKET_FANOUT_LB:
1462
		idx = fanout_demux_lb(f, skb, num);
1463 1464
		break;
	case PACKET_FANOUT_CPU:
1465 1466
		idx = fanout_demux_cpu(f, skb, num);
		break;
1467 1468 1469
	case PACKET_FANOUT_RND:
		idx = fanout_demux_rnd(f, skb, num);
		break;
1470 1471 1472
	case PACKET_FANOUT_QM:
		idx = fanout_demux_qm(f, skb, num);
		break;
1473
	case PACKET_FANOUT_ROLLOVER:
1474
		idx = fanout_demux_rollover(f, skb, 0, false, num);
1475
		break;
1476
	case PACKET_FANOUT_CBPF:
1477
	case PACKET_FANOUT_EBPF:
1478 1479
		idx = fanout_demux_bpf(f, skb, num);
		break;
D
David S. Miller 已提交
1480 1481
	}

1482 1483
	if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
		idx = fanout_demux_rollover(f, skb, idx, true, num);
D
David S. Miller 已提交
1484

1485
	po = pkt_sk(f->arr[idx]);
D
David S. Miller 已提交
1486 1487 1488
	return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
}

1489 1490
DEFINE_MUTEX(fanout_mutex);
EXPORT_SYMBOL_GPL(fanout_mutex);
D
David S. Miller 已提交
1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519
static LIST_HEAD(fanout_list);

static void __fanout_link(struct sock *sk, struct packet_sock *po)
{
	struct packet_fanout *f = po->fanout;

	spin_lock(&f->lock);
	f->arr[f->num_members] = sk;
	smp_wmb();
	f->num_members++;
	spin_unlock(&f->lock);
}

static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
{
	struct packet_fanout *f = po->fanout;
	int i;

	spin_lock(&f->lock);
	for (i = 0; i < f->num_members; i++) {
		if (f->arr[i] == sk)
			break;
	}
	BUG_ON(i >= f->num_members);
	f->arr[i] = f->arr[f->num_members - 1];
	f->num_members--;
	spin_unlock(&f->lock);
}

1520
static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1521
{
1522
	if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1523 1524 1525 1526 1527
		return true;

	return false;
}

1528 1529 1530 1531 1532 1533 1534
static void fanout_init_data(struct packet_fanout *f)
{
	switch (f->type) {
	case PACKET_FANOUT_LB:
		atomic_set(&f->rr_cur, 0);
		break;
	case PACKET_FANOUT_CBPF:
1535
	case PACKET_FANOUT_EBPF:
1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569
		RCU_INIT_POINTER(f->bpf_prog, NULL);
		break;
	}
}

static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
{
	struct bpf_prog *old;

	spin_lock(&f->lock);
	old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
	rcu_assign_pointer(f->bpf_prog, new);
	spin_unlock(&f->lock);

	if (old) {
		synchronize_net();
		bpf_prog_destroy(old);
	}
}

static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
				unsigned int len)
{
	struct bpf_prog *new;
	struct sock_fprog fprog;
	int ret;

	if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
		return -EPERM;
	if (len != sizeof(fprog))
		return -EINVAL;
	if (copy_from_user(&fprog, data, len))
		return -EFAULT;

1570
	ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1571 1572 1573 1574 1575 1576 1577
	if (ret)
		return ret;

	__fanout_set_data_bpf(po->fanout, new);
	return 0;
}

1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602
static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
				unsigned int len)
{
	struct bpf_prog *new;
	u32 fd;

	if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
		return -EPERM;
	if (len != sizeof(fd))
		return -EINVAL;
	if (copy_from_user(&fd, data, len))
		return -EFAULT;

	new = bpf_prog_get(fd);
	if (IS_ERR(new))
		return PTR_ERR(new);
	if (new->type != BPF_PROG_TYPE_SOCKET_FILTER) {
		bpf_prog_put(new);
		return -EINVAL;
	}

	__fanout_set_data_bpf(po->fanout, new);
	return 0;
}

1603 1604 1605 1606 1607 1608
static int fanout_set_data(struct packet_sock *po, char __user *data,
			   unsigned int len)
{
	switch (po->fanout->type) {
	case PACKET_FANOUT_CBPF:
		return fanout_set_data_cbpf(po, data, len);
1609 1610
	case PACKET_FANOUT_EBPF:
		return fanout_set_data_ebpf(po, data, len);
1611 1612 1613 1614 1615 1616 1617 1618 1619
	default:
		return -EINVAL;
	};
}

static void fanout_release_data(struct packet_fanout *f)
{
	switch (f->type) {
	case PACKET_FANOUT_CBPF:
1620
	case PACKET_FANOUT_EBPF:
1621 1622 1623 1624
		__fanout_set_data_bpf(f, NULL);
	};
}

1625
static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
D
David S. Miller 已提交
1626 1627 1628
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_fanout *f, *match;
1629
	u8 type = type_flags & 0xff;
1630
	u8 flags = type_flags >> 8;
D
David S. Miller 已提交
1631 1632 1633
	int err;

	switch (type) {
1634 1635 1636
	case PACKET_FANOUT_ROLLOVER:
		if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
			return -EINVAL;
D
David S. Miller 已提交
1637 1638
	case PACKET_FANOUT_HASH:
	case PACKET_FANOUT_LB:
1639
	case PACKET_FANOUT_CPU:
1640
	case PACKET_FANOUT_RND:
1641
	case PACKET_FANOUT_QM:
1642
	case PACKET_FANOUT_CBPF:
1643
	case PACKET_FANOUT_EBPF:
D
David S. Miller 已提交
1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654
		break;
	default:
		return -EINVAL;
	}

	if (!po->running)
		return -EINVAL;

	if (po->fanout)
		return -EALREADY;

1655 1656
	if (type == PACKET_FANOUT_ROLLOVER ||
	    (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1657 1658 1659
		po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL);
		if (!po->rollover)
			return -ENOMEM;
W
Willem de Bruijn 已提交
1660 1661 1662
		atomic_long_set(&po->rollover->num, 0);
		atomic_long_set(&po->rollover->num_huge, 0);
		atomic_long_set(&po->rollover->num_failed, 0);
1663 1664
	}

D
David S. Miller 已提交
1665 1666 1667 1668 1669 1670 1671 1672 1673
	mutex_lock(&fanout_mutex);
	match = NULL;
	list_for_each_entry(f, &fanout_list, list) {
		if (f->id == id &&
		    read_pnet(&f->net) == sock_net(sk)) {
			match = f;
			break;
		}
	}
E
Eric Dumazet 已提交
1674
	err = -EINVAL;
1675
	if (match && match->flags != flags)
E
Eric Dumazet 已提交
1676
		goto out;
D
David S. Miller 已提交
1677
	if (!match) {
E
Eric Dumazet 已提交
1678
		err = -ENOMEM;
D
David S. Miller 已提交
1679
		match = kzalloc(sizeof(*match), GFP_KERNEL);
E
Eric Dumazet 已提交
1680 1681 1682 1683 1684
		if (!match)
			goto out;
		write_pnet(&match->net, sock_net(sk));
		match->id = id;
		match->type = type;
1685
		match->flags = flags;
E
Eric Dumazet 已提交
1686 1687 1688
		INIT_LIST_HEAD(&match->list);
		spin_lock_init(&match->lock);
		atomic_set(&match->sk_ref, 0);
1689
		fanout_init_data(match);
E
Eric Dumazet 已提交
1690 1691 1692 1693
		match->prot_hook.type = po->prot_hook.type;
		match->prot_hook.dev = po->prot_hook.dev;
		match->prot_hook.func = packet_rcv_fanout;
		match->prot_hook.af_packet_priv = match;
1694
		match->prot_hook.id_match = match_fanout_group;
E
Eric Dumazet 已提交
1695 1696
		dev_add_pack(&match->prot_hook);
		list_add(&match->list, &fanout_list);
D
David S. Miller 已提交
1697
	}
E
Eric Dumazet 已提交
1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708
	err = -EINVAL;
	if (match->type == type &&
	    match->prot_hook.type == po->prot_hook.type &&
	    match->prot_hook.dev == po->prot_hook.dev) {
		err = -ENOSPC;
		if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
			__dev_remove_pack(&po->prot_hook);
			po->fanout = match;
			atomic_inc(&match->sk_ref);
			__fanout_link(sk, po);
			err = 0;
D
David S. Miller 已提交
1709 1710
		}
	}
E
Eric Dumazet 已提交
1711
out:
D
David S. Miller 已提交
1712
	mutex_unlock(&fanout_mutex);
1713 1714 1715 1716
	if (err) {
		kfree(po->rollover);
		po->rollover = NULL;
	}
D
David S. Miller 已提交
1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728
	return err;
}

static void fanout_release(struct sock *sk)
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_fanout *f;

	f = po->fanout;
	if (!f)
		return;

1729
	mutex_lock(&fanout_mutex);
D
David S. Miller 已提交
1730 1731 1732 1733 1734
	po->fanout = NULL;

	if (atomic_dec_and_test(&f->sk_ref)) {
		list_del(&f->list);
		dev_remove_pack(&f->prot_hook);
1735
		fanout_release_data(f);
D
David S. Miller 已提交
1736 1737 1738
		kfree(f);
	}
	mutex_unlock(&fanout_mutex);
1739

1740 1741
	if (po->rollover)
		kfree_rcu(po->rollover, rcu);
D
David S. Miller 已提交
1742
}
L
Linus Torvalds 已提交
1743

1744
static const struct proto_ops packet_ops;
L
Linus Torvalds 已提交
1745

1746
static const struct proto_ops packet_ops_spkt;
L
Linus Torvalds 已提交
1747

E
Eric Dumazet 已提交
1748 1749
static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
{
	struct sock *sk;
	struct sockaddr_pkt *spkt;

	/*
	 *	When we registered the protocol we saved the socket in the data
	 *	field for just this event.
	 */

	sk = pt->af_packet_priv;
1760

L
Linus Torvalds 已提交
1761 1762 1763 1764 1765 1766 1767
	/*
	 *	Yank back the headers [hope the device set this
	 *	right or kerboom...]
	 *
	 *	Incoming packets have ll header pulled,
	 *	push it back.
	 *
1768
	 *	For outgoing ones skb->data == skb_mac_header(skb)
L
Linus Torvalds 已提交
1769 1770 1771 1772 1773 1774
	 *	so that this procedure is noop.
	 */

	if (skb->pkt_type == PACKET_LOOPBACK)
		goto out;

O
Octavian Purdila 已提交
1775
	if (!net_eq(dev_net(dev), sock_net(sk)))
1776 1777
		goto out;

E
Eric Dumazet 已提交
1778 1779
	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL)
L
Linus Torvalds 已提交
1780 1781 1782
		goto oom;

	/* drop any routing info */
E
Eric Dumazet 已提交
1783
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1784

1785 1786 1787
	/* drop conntrack reference */
	nf_reset(skb);

1788
	spkt = &PACKET_SKB_CB(skb)->sa.pkt;
L
Linus Torvalds 已提交
1789

1790
	skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804

	/*
	 *	The SOCK_PACKET socket receives _all_ frames.
	 */

	spkt->spkt_family = dev->type;
	strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
	spkt->spkt_protocol = skb->protocol;

	/*
	 *	Charge the memory to the socket. This is done specifically
	 *	to prevent sockets using all the memory up.
	 */

E
Eric Dumazet 已提交
1805
	if (sock_queue_rcv_skb(sk, skb) == 0)
L
Linus Torvalds 已提交
1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818
		return 0;

out:
	kfree_skb(skb);
oom:
	return 0;
}


/*
 *	Output a raw packet to a device layer. This bypasses all the other
 *	protocol layers and you must therefore supply it with a complete frame
 */
1819

1820 1821
static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
			       size_t len)
L
Linus Torvalds 已提交
1822 1823
{
	struct sock *sk = sock->sk;
1824
	DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1825
	struct sk_buff *skb = NULL;
L
Linus Torvalds 已提交
1826
	struct net_device *dev;
E
Eric Dumazet 已提交
1827
	__be16 proto = 0;
L
Linus Torvalds 已提交
1828
	int err;
1829
	int extra_len = 0;
1830

L
Linus Torvalds 已提交
1831
	/*
1832
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1833 1834
	 */

E
Eric Dumazet 已提交
1835
	if (saddr) {
L
Linus Torvalds 已提交
1836
		if (msg->msg_namelen < sizeof(struct sockaddr))
E
Eric Dumazet 已提交
1837 1838 1839 1840 1841
			return -EINVAL;
		if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
			proto = saddr->spkt_protocol;
	} else
		return -ENOTCONN;	/* SOCK_PACKET must be sent giving an address */
L
Linus Torvalds 已提交
1842 1843

	/*
1844
	 *	Find the device first to size check it
L
Linus Torvalds 已提交
1845 1846
	 */

1847
	saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1848
retry:
E
Eric Dumazet 已提交
1849 1850
	rcu_read_lock();
	dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
L
Linus Torvalds 已提交
1851 1852 1853
	err = -ENODEV;
	if (dev == NULL)
		goto out_unlock;
1854

1855 1856 1857 1858
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

L
Linus Torvalds 已提交
1859
	/*
E
Eric Dumazet 已提交
1860 1861
	 * You may not queue a frame bigger than the mtu. This is the lowest level
	 * raw protocol and you must do your own fragmentation at this level.
L
Linus Torvalds 已提交
1862
	 */
1863

1864 1865 1866 1867 1868 1869 1870 1871
	if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
		if (!netif_supports_nofcs(dev)) {
			err = -EPROTONOSUPPORT;
			goto out_unlock;
		}
		extra_len = 4; /* We're doing our own CRC */
	}

L
Linus Torvalds 已提交
1872
	err = -EMSGSIZE;
1873
	if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
L
Linus Torvalds 已提交
1874 1875
		goto out_unlock;

1876 1877
	if (!skb) {
		size_t reserved = LL_RESERVED_SPACE(dev);
1878
		int tlen = dev->needed_tailroom;
1879 1880 1881
		unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;

		rcu_read_unlock();
1882
		skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898
		if (skb == NULL)
			return -ENOBUFS;
		/* FIXME: Save some space for broken drivers that write a hard
		 * header at transmission time by themselves. PPP is the notable
		 * one here. This should really be fixed at the driver level.
		 */
		skb_reserve(skb, reserved);
		skb_reset_network_header(skb);

		/* Try to align data part correctly */
		if (hhlen) {
			skb->data -= hhlen;
			skb->tail -= hhlen;
			if (len < hhlen)
				skb_reset_network_header(skb);
		}
A
Al Viro 已提交
1899
		err = memcpy_from_msg(skb_put(skb, len), msg, len);
1900 1901 1902
		if (err)
			goto out_free;
		goto retry;
L
Linus Torvalds 已提交
1903 1904
	}

1905
	if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917
		/* Earlier code assumed this would be a VLAN pkt,
		 * double-check this now that we have the actual
		 * packet in hand.
		 */
		struct ethhdr *ehdr;
		skb_reset_mac_header(skb);
		ehdr = eth_hdr(skb);
		if (ehdr->h_proto != htons(ETH_P_8021Q)) {
			err = -EMSGSIZE;
			goto out_unlock;
		}
	}
1918

L
Linus Torvalds 已提交
1919 1920 1921
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1922
	skb->mark = sk->sk_mark;
1923 1924

	sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
L
Linus Torvalds 已提交
1925

1926 1927 1928
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

1929
	skb_probe_transport_header(skb, 0);
1930

L
Linus Torvalds 已提交
1931
	dev_queue_xmit(skb);
E
Eric Dumazet 已提交
1932
	rcu_read_unlock();
E
Eric Dumazet 已提交
1933
	return len;
L
Linus Torvalds 已提交
1934 1935

out_unlock:
E
Eric Dumazet 已提交
1936
	rcu_read_unlock();
1937 1938
out_free:
	kfree_skb(skb);
L
Linus Torvalds 已提交
1939 1940 1941
	return err;
}

1942 1943 1944
static unsigned int run_filter(struct sk_buff *skb,
			       const struct sock *sk,
			       unsigned int res)
L
Linus Torvalds 已提交
1945 1946
{
	struct sk_filter *filter;
1947

1948 1949
	rcu_read_lock();
	filter = rcu_dereference(sk->sk_filter);
D
David S. Miller 已提交
1950
	if (filter != NULL)
1951
		res = bpf_prog_run_clear_cb(filter->prog, skb);
1952
	rcu_read_unlock();
L
Linus Torvalds 已提交
1953

D
David S. Miller 已提交
1954
	return res;
L
Linus Torvalds 已提交
1955 1956 1957
}

/*
E
Eric Dumazet 已提交
1958 1959 1960 1961 1962 1963 1964 1965 1966
 * This function makes lazy skb cloning in hope that most of packets
 * are discarded by BPF.
 *
 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
 * and skb->cb are mangled. It works because (and until) packets
 * falling here are owned by current CPU. Output packets are cloned
 * by dev_queue_xmit_nit(), input packets are processed by net_bh
 * sequencially, so that if we return skb to original state on exit,
 * we will not harm anyone.
L
Linus Torvalds 已提交
1967 1968
 */

E
Eric Dumazet 已提交
1969 1970
static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
		      struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
1971 1972 1973 1974
{
	struct sock *sk;
	struct sockaddr_ll *sll;
	struct packet_sock *po;
E
Eric Dumazet 已提交
1975
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
1976
	int skb_len = skb->len;
D
David S. Miller 已提交
1977
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
1978 1979 1980 1981 1982 1983 1984

	if (skb->pkt_type == PACKET_LOOPBACK)
		goto drop;

	sk = pt->af_packet_priv;
	po = pkt_sk(sk);

O
Octavian Purdila 已提交
1985
	if (!net_eq(dev_net(dev), sock_net(sk)))
1986 1987
		goto drop;

L
Linus Torvalds 已提交
1988 1989
	skb->dev = dev;

1990
	if (dev->header_ops) {
L
Linus Torvalds 已提交
1991
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
1992 1993 1994 1995 1996
		 * exported to higher levels.
		 *
		 * Otherwise, the device hides details of its frame
		 * structure, so that corresponding packet head is
		 * never delivered to user.
L
Linus Torvalds 已提交
1997 1998
		 */
		if (sk->sk_type != SOCK_DGRAM)
1999
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
2000 2001
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
2002
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
2003 2004 2005 2006 2007
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
2008 2009
	res = run_filter(skb, sk, snaplen);
	if (!res)
2010
		goto drop_n_restore;
D
David S. Miller 已提交
2011 2012
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
2013

E
Eric Dumazet 已提交
2014
	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
L
Linus Torvalds 已提交
2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
		goto drop_n_acct;

	if (skb_shared(skb)) {
		struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
		if (nskb == NULL)
			goto drop_n_acct;

		if (skb_head != skb->data) {
			skb->data = skb_head;
			skb->len = skb_len;
		}
2026
		consume_skb(skb);
L
Linus Torvalds 已提交
2027 2028 2029
		skb = nskb;
	}

2030
	sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2031 2032

	sll = &PACKET_SKB_CB(skb)->sa.ll;
L
Linus Torvalds 已提交
2033 2034
	sll->sll_hatype = dev->type;
	sll->sll_pkttype = skb->pkt_type;
2035
	if (unlikely(po->origdev))
2036 2037 2038
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
2039

S
Stephen Hemminger 已提交
2040
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
2041

2042 2043 2044 2045
	/* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
	 * Use their space for storing the original skb length.
	 */
	PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2046

L
Linus Torvalds 已提交
2047 2048 2049 2050 2051
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
2052
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
2053

2054 2055 2056
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
2057
	spin_lock(&sk->sk_receive_queue.lock);
2058
	po->stats.stats1.tp_packets++;
2059
	sock_skb_set_dropcount(sk, skb);
L
Linus Torvalds 已提交
2060 2061
	__skb_queue_tail(&sk->sk_receive_queue, skb);
	spin_unlock(&sk->sk_receive_queue.lock);
2062
	sk->sk_data_ready(sk);
L
Linus Torvalds 已提交
2063 2064 2065
	return 0;

drop_n_acct:
2066
	spin_lock(&sk->sk_receive_queue.lock);
2067
	po->stats.stats1.tp_drops++;
2068 2069
	atomic_inc(&sk->sk_drops);
	spin_unlock(&sk->sk_receive_queue.lock);
L
Linus Torvalds 已提交
2070 2071 2072 2073 2074 2075 2076

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
2077
	consume_skb(skb);
L
Linus Torvalds 已提交
2078 2079 2080
	return 0;
}

E
Eric Dumazet 已提交
2081 2082
static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
		       struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
2083 2084 2085 2086
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
2087
	union tpacket_uhdr h;
E
Eric Dumazet 已提交
2088
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
2089
	int skb_len = skb->len;
D
David S. Miller 已提交
2090
	unsigned int snaplen, res;
2091
	unsigned long status = TP_STATUS_USER;
2092
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
2093
	struct sk_buff *copy_skb = NULL;
2094
	struct timespec ts;
2095
	__u32 ts_status;
L
Linus Torvalds 已提交
2096

2097 2098 2099 2100 2101 2102 2103
	/* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
	 * We may add members to them until current aligned size without forcing
	 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
	 */
	BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
	BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);

L
Linus Torvalds 已提交
2104 2105 2106 2107 2108 2109
	if (skb->pkt_type == PACKET_LOOPBACK)
		goto drop;

	sk = pt->af_packet_priv;
	po = pkt_sk(sk);

O
Octavian Purdila 已提交
2110
	if (!net_eq(dev_net(dev), sock_net(sk)))
2111 2112
		goto drop;

2113
	if (dev->header_ops) {
L
Linus Torvalds 已提交
2114
		if (sk->sk_type != SOCK_DGRAM)
2115
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
2116 2117
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
2118
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
2119 2120 2121 2122 2123
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
2124 2125
	res = run_filter(skb, sk, snaplen);
	if (!res)
2126
		goto drop_n_restore;
2127 2128 2129

	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;
2130 2131 2132 2133
	else if (skb->pkt_type != PACKET_OUTGOING &&
		 (skb->ip_summed == CHECKSUM_COMPLETE ||
		  skb_csum_unnecessary(skb)))
		status |= TP_STATUS_CSUM_VALID;
2134

D
David S. Miller 已提交
2135 2136
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
2137 2138

	if (sk->sk_type == SOCK_DGRAM) {
2139 2140
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
2141
	} else {
2142
		unsigned int maclen = skb_network_offset(skb);
2143
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
2144 2145
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
2146 2147
		macoff = netoff - maclen;
	}
2148 2149 2150
	if (po->tp_version <= TPACKET_V2) {
		if (macoff + snaplen > po->rx_ring.frame_size) {
			if (po->copy_thresh &&
E
Eric Dumazet 已提交
2151
			    atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2152 2153 2154 2155 2156 2157 2158 2159
				if (skb_shared(skb)) {
					copy_skb = skb_clone(skb, GFP_ATOMIC);
				} else {
					copy_skb = skb_get(skb);
					skb_head = skb->data;
				}
				if (copy_skb)
					skb_set_owner_r(copy_skb, sk);
L
Linus Torvalds 已提交
2160
			}
2161 2162 2163
			snaplen = po->rx_ring.frame_size - macoff;
			if ((int)snaplen < 0)
				snaplen = 0;
L
Linus Torvalds 已提交
2164
		}
2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
	} else if (unlikely(macoff + snaplen >
			    GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
		u32 nval;

		nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
		pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
			    snaplen, nval, macoff);
		snaplen = nval;
		if (unlikely((int)snaplen < 0)) {
			snaplen = 0;
			macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
		}
L
Linus Torvalds 已提交
2177 2178
	}
	spin_lock(&sk->sk_receive_queue.lock);
2179 2180
	h.raw = packet_current_rx_frame(po, skb,
					TP_STATUS_KERNEL, (macoff+snaplen));
2181
	if (!h.raw)
L
Linus Torvalds 已提交
2182
		goto ring_is_full;
2183 2184 2185 2186 2187 2188 2189 2190
	if (po->tp_version <= TPACKET_V2) {
		packet_increment_rx_head(po, &po->rx_ring);
	/*
	 * LOSING will be reported till you read the stats,
	 * because it's COR - Clear On Read.
	 * Anyways, moving it for V1/V2 only as V3 doesn't need this
	 * at packet level.
	 */
2191
		if (po->stats.stats1.tp_drops)
2192 2193
			status |= TP_STATUS_LOSING;
	}
2194
	po->stats.stats1.tp_packets++;
L
Linus Torvalds 已提交
2195 2196 2197 2198 2199 2200
	if (copy_skb) {
		status |= TP_STATUS_COPY;
		__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
	}
	spin_unlock(&sk->sk_receive_queue.lock);

2201
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2202 2203

	if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2204
		getnstimeofday(&ts);
L
Linus Torvalds 已提交
2205

2206 2207
	status |= ts_status;

2208 2209 2210 2211 2212 2213
	switch (po->tp_version) {
	case TPACKET_V1:
		h.h1->tp_len = skb->len;
		h.h1->tp_snaplen = snaplen;
		h.h1->tp_mac = macoff;
		h.h1->tp_net = netoff;
2214 2215
		h.h1->tp_sec = ts.tv_sec;
		h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2216 2217 2218 2219 2220 2221 2222 2223 2224
		hdrlen = sizeof(*h.h1);
		break;
	case TPACKET_V2:
		h.h2->tp_len = skb->len;
		h.h2->tp_snaplen = snaplen;
		h.h2->tp_mac = macoff;
		h.h2->tp_net = netoff;
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
2225 2226
		if (skb_vlan_tag_present(skb)) {
			h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2227 2228
			h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
			status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2229 2230
		} else {
			h.h2->tp_vlan_tci = 0;
2231
			h.h2->tp_vlan_tpid = 0;
2232
		}
2233
		memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2234 2235
		hdrlen = sizeof(*h.h2);
		break;
2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246
	case TPACKET_V3:
		/* tp_nxt_offset,vlan are already populated above.
		 * So DONT clear those fields here
		 */
		h.h3->tp_status |= status;
		h.h3->tp_len = skb->len;
		h.h3->tp_snaplen = snaplen;
		h.h3->tp_mac = macoff;
		h.h3->tp_net = netoff;
		h.h3->tp_sec  = ts.tv_sec;
		h.h3->tp_nsec = ts.tv_nsec;
2247
		memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2248 2249
		hdrlen = sizeof(*h.h3);
		break;
2250 2251 2252
	default:
		BUG();
	}
L
Linus Torvalds 已提交
2253

2254
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
2255
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
2256 2257 2258 2259
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
2260
	if (unlikely(po->origdev))
2261 2262 2263
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
2264

R
Ralf Baechle 已提交
2265
	smp_mb();
2266

2267
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2268
	if (po->tp_version <= TPACKET_V2) {
2269 2270
		u8 *start, *end;

2271 2272 2273 2274 2275
		end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
					macoff + snaplen);

		for (start = h.raw; start < end; start += PAGE_SIZE)
			flush_dcache_page(pgv_to_page(start));
L
Linus Torvalds 已提交
2276
	}
2277
	smp_wmb();
2278
#endif
2279

2280
	if (po->tp_version <= TPACKET_V2) {
2281
		__packet_set_status(po, h.raw, status);
2282 2283
		sk->sk_data_ready(sk);
	} else {
2284
		prb_clear_blk_fill_status(&po->rx_ring);
2285
	}
L
Linus Torvalds 已提交
2286 2287 2288 2289 2290 2291 2292

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
2293
	kfree_skb(skb);
L
Linus Torvalds 已提交
2294 2295 2296
	return 0;

ring_is_full:
2297
	po->stats.stats1.tp_drops++;
L
Linus Torvalds 已提交
2298 2299
	spin_unlock(&sk->sk_receive_queue.lock);

2300
	sk->sk_data_ready(sk);
2301
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
2302 2303 2304
	goto drop_n_restore;
}

J
Johann Baudy 已提交
2305 2306 2307
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
L
Linus Torvalds 已提交
2308

J
Johann Baudy 已提交
2309
	if (likely(po->tx_ring.pg_vec)) {
2310
		void *ph;
2311 2312
		__u32 ts;

J
Johann Baudy 已提交
2313
		ph = skb_shinfo(skb)->destructor_arg;
2314
		packet_dec_pending(&po->tx_ring);
2315 2316 2317

		ts = __packet_set_timestamp(po, ph, skb);
		__packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
J
Johann Baudy 已提交
2318 2319 2320 2321 2322
	}

	sock_wfree(skb);
}

2323 2324 2325 2326
static bool ll_header_truncated(const struct net_device *dev, int len)
{
	/* net device doesn't like empty head */
	if (unlikely(len <= dev->hard_header_len)) {
2327
		net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n",
2328 2329 2330 2331 2332 2333 2334
				     current->comm, len, dev->hard_header_len);
		return true;
	}

	return false;
}

E
Eric Dumazet 已提交
2335 2336
static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
		void *frame, struct net_device *dev, int size_max,
2337
		__be16 proto, unsigned char *addr, int hlen)
J
Johann Baudy 已提交
2338
{
2339
	union tpacket_uhdr ph;
2340
	int to_write, offset, len, tp_len, nr_frags, len_max;
J
Johann Baudy 已提交
2341 2342 2343 2344 2345 2346 2347 2348 2349 2350
	struct socket *sock = po->sk.sk_socket;
	struct page *page;
	void *data;
	int err;

	ph.raw = frame;

	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = po->sk.sk_priority;
2351
	skb->mark = po->sk.sk_mark;
2352
	sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
J
Johann Baudy 已提交
2353 2354 2355 2356 2357 2358 2359 2360 2361 2362
	skb_shinfo(skb)->destructor_arg = ph.raw;

	switch (po->tp_version) {
	case TPACKET_V2:
		tp_len = ph.h2->tp_len;
		break;
	default:
		tp_len = ph.h1->tp_len;
		break;
	}
2363 2364 2365 2366
	if (unlikely(tp_len > size_max)) {
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
		return -EMSGSIZE;
	}
J
Johann Baudy 已提交
2367

2368
	skb_reserve(skb, hlen);
J
Johann Baudy 已提交
2369
	skb_reset_network_header(skb);
2370

2371 2372 2373
	if (!packet_use_direct_xmit(po))
		skb_probe_transport_header(skb, 0);
	if (unlikely(po->tp_tx_has_off)) {
2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401
		int off_min, off_max, off;
		off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
		off_max = po->tx_ring.frame_size - tp_len;
		if (sock->type == SOCK_DGRAM) {
			switch (po->tp_version) {
			case TPACKET_V2:
				off = ph.h2->tp_net;
				break;
			default:
				off = ph.h1->tp_net;
				break;
			}
		} else {
			switch (po->tp_version) {
			case TPACKET_V2:
				off = ph.h2->tp_mac;
				break;
			default:
				off = ph.h1->tp_mac;
				break;
			}
		}
		if (unlikely((off < off_min) || (off_max < off)))
			return -EINVAL;
		data = ph.raw + off;
	} else {
		data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
	}
J
Johann Baudy 已提交
2402 2403 2404 2405 2406 2407 2408
	to_write = tp_len;

	if (sock->type == SOCK_DGRAM) {
		err = dev_hard_header(skb, dev, ntohs(proto), addr,
				NULL, tp_len);
		if (unlikely(err < 0))
			return -EINVAL;
E
Eric Dumazet 已提交
2409
	} else if (dev->hard_header_len) {
2410
		if (ll_header_truncated(dev, tp_len))
J
Johann Baudy 已提交
2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435
			return -EINVAL;

		skb_push(skb, dev->hard_header_len);
		err = skb_store_bits(skb, 0, data,
				dev->hard_header_len);
		if (unlikely(err))
			return err;

		data += dev->hard_header_len;
		to_write -= dev->hard_header_len;
	}

	offset = offset_in_page(data);
	len_max = PAGE_SIZE - offset;
	len = ((to_write > len_max) ? len_max : to_write);

	skb->data_len = to_write;
	skb->len += to_write;
	skb->truesize += to_write;
	atomic_add(to_write, &po->sk.sk_wmem_alloc);

	while (likely(to_write)) {
		nr_frags = skb_shinfo(skb)->nr_frags;

		if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
E
Eric Dumazet 已提交
2436 2437
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
2438 2439 2440
			return -EFAULT;
		}

2441 2442
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
2443 2444
		flush_dcache_page(page);
		get_page(page);
2445
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
		to_write -= len;
		offset = 0;
		len_max = PAGE_SIZE;
		len = ((to_write > len_max) ? len_max : to_write);
	}

	return tp_len;
}

static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
{
	struct sk_buff *skb;
	struct net_device *dev;
	__be16 proto;
2460
	int err, reserve = 0;
E
Eric Dumazet 已提交
2461
	void *ph;
2462
	DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2463
	bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
J
Johann Baudy 已提交
2464 2465 2466
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
2467
	int status = TP_STATUS_AVAILABLE;
2468
	int hlen, tlen;
J
Johann Baudy 已提交
2469 2470 2471

	mutex_lock(&po->pg_vec_lock);

2472
	if (likely(saddr == NULL)) {
2473
		dev	= packet_cached_dev_get(po);
J
Johann Baudy 已提交
2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
		if (msg->msg_namelen < (saddr->sll_halen
					+ offsetof(struct sockaddr_ll,
						sll_addr)))
			goto out;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
2486
		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
J
Johann Baudy 已提交
2487 2488 2489 2490 2491 2492 2493 2494 2495
	}

	err = -ENXIO;
	if (unlikely(dev == NULL))
		goto out;
	err = -ENETDOWN;
	if (unlikely(!(dev->flags & IFF_UP)))
		goto out_put;

2496
	reserve = dev->hard_header_len + VLAN_HLEN;
J
Johann Baudy 已提交
2497
	size_max = po->tx_ring.frame_size
2498
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
2499

2500 2501 2502
	if (size_max > dev->mtu + reserve)
		size_max = dev->mtu + reserve;

J
Johann Baudy 已提交
2503 2504
	do {
		ph = packet_current_frame(po, &po->tx_ring,
2505
					  TP_STATUS_SEND_REQUEST);
J
Johann Baudy 已提交
2506
		if (unlikely(ph == NULL)) {
2507 2508
			if (need_wait && need_resched())
				schedule();
J
Johann Baudy 已提交
2509 2510 2511 2512
			continue;
		}

		status = TP_STATUS_SEND_REQUEST;
2513 2514
		hlen = LL_RESERVED_SPACE(dev);
		tlen = dev->needed_tailroom;
J
Johann Baudy 已提交
2515
		skb = sock_alloc_send_skb(&po->sk,
2516
				hlen + tlen + sizeof(struct sockaddr_ll),
2517
				!need_wait, &err);
J
Johann Baudy 已提交
2518

2519 2520 2521 2522
		if (unlikely(skb == NULL)) {
			/* we assume the socket was initially writeable ... */
			if (likely(len_sum > 0))
				err = len_sum;
J
Johann Baudy 已提交
2523
			goto out_status;
2524
		}
J
Johann Baudy 已提交
2525
		tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2526
					  addr, hlen);
2527 2528
		if (likely(tp_len >= 0) &&
		    tp_len > dev->mtu + dev->hard_header_len) {
2529 2530 2531 2532 2533
			struct ethhdr *ehdr;
			/* Earlier code assumed this would be a VLAN pkt,
			 * double-check this now that we have the actual
			 * packet in hand.
			 */
J
Johann Baudy 已提交
2534

2535 2536 2537 2538 2539
			skb_reset_mac_header(skb);
			ehdr = eth_hdr(skb);
			if (ehdr->h_proto != htons(ETH_P_8021Q))
				tp_len = -EMSGSIZE;
		}
J
Johann Baudy 已提交
2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553
		if (unlikely(tp_len < 0)) {
			if (po->tp_loss) {
				__packet_set_status(po, ph,
						TP_STATUS_AVAILABLE);
				packet_increment_head(&po->tx_ring);
				kfree_skb(skb);
				continue;
			} else {
				status = TP_STATUS_WRONG_FORMAT;
				err = tp_len;
				goto out_status;
			}
		}

2554 2555
		packet_pick_tx_queue(dev, skb);

J
Johann Baudy 已提交
2556 2557
		skb->destructor = tpacket_destruct_skb;
		__packet_set_status(po, ph, TP_STATUS_SENDING);
2558
		packet_inc_pending(&po->tx_ring);
J
Johann Baudy 已提交
2559 2560

		status = TP_STATUS_SEND_REQUEST;
2561
		err = po->xmit(skb);
2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575
		if (unlikely(err > 0)) {
			err = net_xmit_errno(err);
			if (err && __packet_get_status(po, ph) ==
				   TP_STATUS_AVAILABLE) {
				/* skb was destructed already */
				skb = NULL;
				goto out_status;
			}
			/*
			 * skb was dropped but not destructed yet;
			 * let's treat it like congestion or err < 0
			 */
			err = 0;
		}
J
Johann Baudy 已提交
2576 2577
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
2578 2579 2580 2581 2582 2583 2584 2585
	} while (likely((ph != NULL) ||
		/* Note: packet_read_pending() might be slow if we have
		 * to call it as it's per_cpu variable, but in fast-path
		 * we already short-circuit the loop with the first
		 * condition, and luckily don't have to go that path
		 * anyway.
		 */
		 (need_wait && packet_read_pending(&po->tx_ring))));
J
Johann Baudy 已提交
2586 2587 2588 2589 2590 2591 2592 2593

	err = len_sum;
	goto out_put;

out_status:
	__packet_set_status(po, ph, status);
	kfree_skb(skb);
out_put:
2594
	dev_put(dev);
J
Johann Baudy 已提交
2595 2596 2597 2598 2599
out:
	mutex_unlock(&po->pg_vec_lock);
	return err;
}

2600 2601 2602 2603
static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
				        size_t reserve, size_t len,
				        size_t linear, int noblock,
				        int *err)
2604 2605 2606 2607 2608 2609 2610 2611
{
	struct sk_buff *skb;

	/* Under a page?  Don't bother with paged skb. */
	if (prepad + len < PAGE_SIZE || !linear)
		linear = len;

	skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2612
				   err, 0);
2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623
	if (!skb)
		return NULL;

	skb_reserve(skb, reserve);
	skb_put(skb, linear);
	skb->data_len = len - linear;
	skb->len += len - linear;

	return skb;
}

2624
static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
L
Linus Torvalds 已提交
2625 2626
{
	struct sock *sk = sock->sk;
2627
	DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
L
Linus Torvalds 已提交
2628 2629
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
2630
	__be16 proto;
L
Linus Torvalds 已提交
2631
	unsigned char *addr;
2632
	int err, reserve = 0;
2633
	struct sockcm_cookie sockc;
2634 2635 2636 2637 2638
	struct virtio_net_hdr vnet_hdr = { 0 };
	int offset = 0;
	int vnet_hdr_len;
	struct packet_sock *po = pkt_sk(sk);
	unsigned short gso_type = 0;
2639
	int hlen, tlen;
2640
	int extra_len = 0;
2641
	ssize_t n;
L
Linus Torvalds 已提交
2642 2643

	/*
2644
	 *	Get and verify the address.
L
Linus Torvalds 已提交
2645
	 */
2646

2647
	if (likely(saddr == NULL)) {
2648
		dev	= packet_cached_dev_get(po);
L
Linus Torvalds 已提交
2649 2650 2651 2652 2653 2654
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
2655 2656
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
2657 2658
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
2659
		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
L
Linus Torvalds 已提交
2660 2661 2662
	}

	err = -ENXIO;
2663
	if (unlikely(dev == NULL))
L
Linus Torvalds 已提交
2664
		goto out_unlock;
2665
	err = -ENETDOWN;
2666
	if (unlikely(!(dev->flags & IFF_UP)))
2667 2668
		goto out_unlock;

2669 2670 2671 2672 2673 2674 2675
	sockc.mark = sk->sk_mark;
	if (msg->msg_controllen) {
		err = sock_cmsg_send(sk, msg, &sockc);
		if (unlikely(err))
			goto out_unlock;
	}

2676 2677
	if (sock->type == SOCK_RAW)
		reserve = dev->hard_header_len;
2678 2679 2680 2681 2682 2683 2684 2685 2686
	if (po->has_vnet_hdr) {
		vnet_hdr_len = sizeof(vnet_hdr);

		err = -EINVAL;
		if (len < vnet_hdr_len)
			goto out_unlock;

		len -= vnet_hdr_len;

2687
		err = -EFAULT;
A
Al Viro 已提交
2688
		n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter);
2689
		if (n != vnet_hdr_len)
2690 2691 2692
			goto out_unlock;

		if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2693 2694 2695 2696 2697 2698
		    (__virtio16_to_cpu(vio_le(), vnet_hdr.csum_start) +
		     __virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset) + 2 >
		      __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len)))
			vnet_hdr.hdr_len = __cpu_to_virtio16(vio_le(),
				 __virtio16_to_cpu(vio_le(), vnet_hdr.csum_start) +
				__virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset) + 2);
2699 2700

		err = -EINVAL;
2701
		if (__virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len) > len)
2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727
			goto out_unlock;

		if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
			switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
			case VIRTIO_NET_HDR_GSO_TCPV4:
				gso_type = SKB_GSO_TCPV4;
				break;
			case VIRTIO_NET_HDR_GSO_TCPV6:
				gso_type = SKB_GSO_TCPV6;
				break;
			case VIRTIO_NET_HDR_GSO_UDP:
				gso_type = SKB_GSO_UDP;
				break;
			default:
				goto out_unlock;
			}

			if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
				gso_type |= SKB_GSO_TCP_ECN;

			if (vnet_hdr.gso_size == 0)
				goto out_unlock;

		}
	}

2728 2729 2730 2731 2732 2733 2734 2735
	if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
		if (!netif_supports_nofcs(dev)) {
			err = -EPROTONOSUPPORT;
			goto out_unlock;
		}
		extra_len = 4; /* We're doing our own CRC */
	}

L
Linus Torvalds 已提交
2736
	err = -EMSGSIZE;
2737
	if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
L
Linus Torvalds 已提交
2738 2739
		goto out_unlock;

2740
	err = -ENOBUFS;
2741 2742
	hlen = LL_RESERVED_SPACE(dev);
	tlen = dev->needed_tailroom;
M
Michael S. Tsirkin 已提交
2743
	skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
2744
			       __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len),
2745
			       msg->msg_flags & MSG_DONTWAIT, &err);
E
Eric Dumazet 已提交
2746
	if (skb == NULL)
L
Linus Torvalds 已提交
2747 2748
		goto out_unlock;

2749
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
2750

2751
	err = -EINVAL;
2752 2753
	if (sock->type == SOCK_DGRAM) {
		offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2754
		if (unlikely(offset < 0))
2755 2756 2757 2758 2759
			goto out_free;
	} else {
		if (ll_header_truncated(dev, len))
			goto out_free;
	}
L
Linus Torvalds 已提交
2760 2761

	/* Returns -EFAULT on error */
A
Al Viro 已提交
2762
	err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
L
Linus Torvalds 已提交
2763 2764
	if (err)
		goto out_free;
2765 2766

	sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
L
Linus Torvalds 已提交
2767

2768
	if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779
		/* Earlier code assumed this would be a VLAN pkt,
		 * double-check this now that we have the actual
		 * packet in hand.
		 */
		struct ethhdr *ehdr;
		skb_reset_mac_header(skb);
		ehdr = eth_hdr(skb);
		if (ehdr->h_proto != htons(ETH_P_8021Q)) {
			err = -EMSGSIZE;
			goto out_free;
		}
2780 2781
	}

2782 2783
	skb->protocol = proto;
	skb->dev = dev;
L
Linus Torvalds 已提交
2784
	skb->priority = sk->sk_priority;
2785
	skb->mark = sockc.mark;
2786 2787

	packet_pick_tx_queue(dev, skb);
L
Linus Torvalds 已提交
2788

2789 2790
	if (po->has_vnet_hdr) {
		if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2791 2792
			u16 s = __virtio16_to_cpu(vio_le(), vnet_hdr.csum_start);
			u16 o = __virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset);
M
Michael S. Tsirkin 已提交
2793
			if (!skb_partial_csum_set(skb, s, o)) {
2794 2795 2796 2797 2798
				err = -EINVAL;
				goto out_free;
			}
		}

M
Michael S. Tsirkin 已提交
2799
		skb_shinfo(skb)->gso_size =
2800
			__virtio16_to_cpu(vio_le(), vnet_hdr.gso_size);
2801 2802 2803 2804 2805 2806 2807 2808 2809
		skb_shinfo(skb)->gso_type = gso_type;

		/* Header must be checked, and gso_segs computed. */
		skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
		skb_shinfo(skb)->gso_segs = 0;

		len += vnet_hdr_len;
	}

2810 2811
	if (!packet_use_direct_xmit(po))
		skb_probe_transport_header(skb, reserve);
2812 2813 2814
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

2815
	err = po->xmit(skb);
L
Linus Torvalds 已提交
2816 2817 2818
	if (err > 0 && (err = net_xmit_errno(err)) != 0)
		goto out_unlock;

2819
	dev_put(dev);
L
Linus Torvalds 已提交
2820

E
Eric Dumazet 已提交
2821
	return len;
L
Linus Torvalds 已提交
2822 2823 2824 2825

out_free:
	kfree_skb(skb);
out_unlock:
2826
	if (dev)
L
Linus Torvalds 已提交
2827 2828 2829 2830 2831
		dev_put(dev);
out:
	return err;
}

2832
static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
J
Johann Baudy 已提交
2833 2834 2835
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
2836

J
Johann Baudy 已提交
2837 2838 2839 2840 2841 2842
	if (po->tx_ring.pg_vec)
		return tpacket_snd(po, msg);
	else
		return packet_snd(sock, msg, len);
}

L
Linus Torvalds 已提交
2843 2844 2845 2846 2847 2848 2849 2850 2851
/*
 *	Close a PACKET socket. This is fairly simple. We immediately go
 *	to 'closed' state and remove our protocol entry in the device list.
 */

static int packet_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po;
2852
	struct net *net;
2853
	union tpacket_req_u req_u;
L
Linus Torvalds 已提交
2854 2855 2856 2857

	if (!sk)
		return 0;

2858
	net = sock_net(sk);
L
Linus Torvalds 已提交
2859 2860
	po = pkt_sk(sk);

2861
	mutex_lock(&net->packet.sklist_lock);
2862
	sk_del_node_init_rcu(sk);
2863 2864 2865
	mutex_unlock(&net->packet.sklist_lock);

	preempt_disable();
2866
	sock_prot_inuse_add(net, sk->sk_prot, -1);
2867
	preempt_enable();
L
Linus Torvalds 已提交
2868

2869
	spin_lock(&po->bind_lock);
2870
	unregister_prot_hook(sk, false);
2871 2872
	packet_cached_dev_reset(po);

2873 2874 2875 2876
	if (po->prot_hook.dev) {
		dev_put(po->prot_hook.dev);
		po->prot_hook.dev = NULL;
	}
2877
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
2878 2879 2880

	packet_flush_mclist(sk);

2881 2882
	if (po->rx_ring.pg_vec) {
		memset(&req_u, 0, sizeof(req_u));
2883
		packet_set_ring(sk, &req_u, 1, 0);
2884
	}
J
Johann Baudy 已提交
2885

2886 2887
	if (po->tx_ring.pg_vec) {
		memset(&req_u, 0, sizeof(req_u));
2888
		packet_set_ring(sk, &req_u, 1, 1);
2889
	}
L
Linus Torvalds 已提交
2890

D
David S. Miller 已提交
2891 2892
	fanout_release(sk);

2893
	synchronize_net();
L
Linus Torvalds 已提交
2894 2895 2896 2897 2898 2899 2900 2901 2902
	/*
	 *	Now the socket is dead. No more input will appear.
	 */
	sock_orphan(sk);
	sock->sk = NULL;

	/* Purge queues */

	skb_queue_purge(&sk->sk_receive_queue);
2903
	packet_free_pending(po);
2904
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
2905 2906 2907 2908 2909 2910 2911 2912 2913

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

2914
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
L
Linus Torvalds 已提交
2915 2916
{
	struct packet_sock *po = pkt_sk(sk);
2917
	struct net_device *dev_curr;
2918 2919
	__be16 proto_curr;
	bool need_rehook;
D
David S. Miller 已提交
2920

2921 2922 2923 2924
	if (po->fanout) {
		if (dev)
			dev_put(dev);

D
David S. Miller 已提交
2925
		return -EINVAL;
2926
	}
L
Linus Torvalds 已提交
2927 2928 2929

	lock_sock(sk);
	spin_lock(&po->bind_lock);
2930

2931 2932 2933 2934 2935 2936 2937
	proto_curr = po->prot_hook.type;
	dev_curr = po->prot_hook.dev;

	need_rehook = proto_curr != proto || dev_curr != dev;

	if (need_rehook) {
		unregister_prot_hook(sk, true);
L
Linus Torvalds 已提交
2938

2939 2940 2941 2942 2943 2944 2945
		po->num = proto;
		po->prot_hook.type = proto;
		po->prot_hook.dev = dev;

		po->ifindex = dev ? dev->ifindex : 0;
		packet_cached_dev_assign(po, dev);
	}
2946 2947
	if (dev_curr)
		dev_put(dev_curr);
2948

2949
	if (proto == 0 || !need_rehook)
L
Linus Torvalds 已提交
2950 2951
		goto out_unlock;

2952
	if (!dev || (dev->flags & IFF_UP)) {
2953
		register_prot_hook(sk);
2954 2955 2956 2957
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969
	}

out_unlock:
	spin_unlock(&po->bind_lock);
	release_sock(sk);
	return 0;
}

/*
 *	Bind a packet socket to a device
 */

E
Eric Dumazet 已提交
2970 2971
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
2972
{
E
Eric Dumazet 已提交
2973
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2974 2975 2976
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
2977

L
Linus Torvalds 已提交
2978 2979 2980
	/*
	 *	Check legality
	 */
2981

2982
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
2983
		return -EINVAL;
E
Eric Dumazet 已提交
2984
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
2985

2986
	dev = dev_get_by_name(sock_net(sk), name);
2987
	if (dev)
L
Linus Torvalds 已提交
2988 2989 2990 2991 2992 2993
		err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
	return err;
}

static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
E
Eric Dumazet 已提交
2994 2995
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2996 2997 2998 2999 3000 3001 3002
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
3003

L
Linus Torvalds 已提交
3004 3005 3006 3007 3008 3009 3010
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
3011
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027
		if (dev == NULL)
			goto out;
	}
	err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);

out:
	return err;
}

static struct proto packet_proto = {
	.name	  = "PACKET",
	.owner	  = THIS_MODULE,
	.obj_size = sizeof(struct packet_sock),
};

/*
3028
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
3029 3030
 */

3031 3032
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
3033 3034 3035
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
3036
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
3037 3038
	int err;

3039
	if (!ns_capable(net->user_ns, CAP_NET_RAW))
L
Linus Torvalds 已提交
3040
		return -EPERM;
3041 3042
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
3043 3044 3045 3046 3047
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
3048
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
L
Linus Torvalds 已提交
3049 3050 3051 3052 3053 3054
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
3055

L
Linus Torvalds 已提交
3056 3057 3058 3059
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
3060
	po->num = proto;
3061
	po->xmit = dev_queue_xmit;
3062

3063 3064 3065 3066
	err = packet_alloc_pending(po);
	if (err)
		goto out2;

3067
	packet_cached_dev_reset(po);
L
Linus Torvalds 已提交
3068 3069

	sk->sk_destruct = packet_sock_destruct;
3070
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
3071 3072 3073 3074 3075 3076

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
3077
	mutex_init(&po->pg_vec_lock);
3078
	po->rollover = NULL;
L
Linus Torvalds 已提交
3079
	po->prot_hook.func = packet_rcv;
3080

L
Linus Torvalds 已提交
3081 3082
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
3083

L
Linus Torvalds 已提交
3084 3085
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
3086 3087
	if (proto) {
		po->prot_hook.type = proto;
3088
		register_prot_hook(sk);
L
Linus Torvalds 已提交
3089 3090
	}

3091
	mutex_lock(&net->packet.sklist_lock);
3092
	sk_add_node_rcu(sk, &net->packet.sklist);
3093 3094 3095
	mutex_unlock(&net->packet.sklist_lock);

	preempt_disable();
3096
	sock_prot_inuse_add(net, &packet_proto, 1);
3097
	preempt_enable();
3098

E
Eric Dumazet 已提交
3099
	return 0;
3100 3101
out2:
	sk_free(sk);
L
Linus Torvalds 已提交
3102 3103 3104 3105 3106 3107 3108 3109 3110
out:
	return err;
}

/*
 *	Pull a packet from our receive queue and hand it to the user.
 *	If necessary we block.
 */

3111 3112
static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
			  int flags)
L
Linus Torvalds 已提交
3113 3114 3115 3116
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied, err;
3117
	int vnet_hdr_len = 0;
3118
	unsigned int origlen = 0;
L
Linus Torvalds 已提交
3119 3120

	err = -EINVAL;
3121
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
3122 3123 3124 3125 3126 3127 3128 3129
		goto out;

#if 0
	/* What error should we return now? EUNATTACH? */
	if (pkt_sk(sk)->ifindex < 0)
		return -ENODEV;
#endif

3130
	if (flags & MSG_ERRQUEUE) {
3131 3132
		err = sock_recv_errqueue(sk, msg, len,
					 SOL_PACKET, PACKET_TX_TIMESTAMP);
3133 3134 3135
		goto out;
	}

L
Linus Torvalds 已提交
3136 3137 3138 3139 3140 3141 3142 3143 3144
	/*
	 *	Call the generic datagram receiver. This handles all sorts
	 *	of horrible races and re-entrancy so we can forget about it
	 *	in the protocol layers.
	 *
	 *	Now it will return ENETDOWN, if device have just gone down,
	 *	but then it will block.
	 */

E
Eric Dumazet 已提交
3145
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
3146 3147

	/*
3148
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
3149 3150 3151 3152
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

3153
	if (skb == NULL)
L
Linus Torvalds 已提交
3154 3155
		goto out;

3156 3157 3158
	if (pkt_sk(sk)->pressure)
		packet_rcv_has_room(pkt_sk(sk), NULL);

3159 3160 3161 3162 3163
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
3164
		if (len < vnet_hdr_len)
3165 3166
			goto out_free;

3167 3168
		len -= vnet_hdr_len;

3169 3170 3171 3172
		if (skb_is_gso(skb)) {
			struct skb_shared_info *sinfo = skb_shinfo(skb);

			/* This is a hint as to how much should be linear. */
M
Michael S. Tsirkin 已提交
3173
			vnet_hdr.hdr_len =
3174
				__cpu_to_virtio16(vio_le(), skb_headlen(skb));
M
Michael S. Tsirkin 已提交
3175
			vnet_hdr.gso_size =
3176
				__cpu_to_virtio16(vio_le(), sinfo->gso_size);
3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193
			if (sinfo->gso_type & SKB_GSO_TCPV4)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
			else if (sinfo->gso_type & SKB_GSO_TCPV6)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
			else if (sinfo->gso_type & SKB_GSO_UDP)
				vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
			else if (sinfo->gso_type & SKB_GSO_FCOE)
				goto out_free;
			else
				BUG();
			if (sinfo->gso_type & SKB_GSO_TCP_ECN)
				vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
		} else
			vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;

		if (skb->ip_summed == CHECKSUM_PARTIAL) {
			vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
3194
			vnet_hdr.csum_start = __cpu_to_virtio16(vio_le(),
M
Michael S. Tsirkin 已提交
3195
					  skb_checksum_start_offset(skb));
3196
			vnet_hdr.csum_offset = __cpu_to_virtio16(vio_le(),
M
Michael S. Tsirkin 已提交
3197
							 skb->csum_offset);
3198 3199
		} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
			vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
3200 3201
		} /* else everything is zero */

A
Al Viro 已提交
3202
		err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
3203 3204 3205 3206
		if (err < 0)
			goto out_free;
	}

3207 3208 3209
	/* You lose any data beyond the buffer you gave. If it worries
	 * a user program they can ask the device for its MTU
	 * anyway.
L
Linus Torvalds 已提交
3210 3211
	 */
	copied = skb->len;
E
Eric Dumazet 已提交
3212 3213 3214
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
3215 3216
	}

3217
	err = skb_copy_datagram_msg(skb, 0, msg, copied);
L
Linus Torvalds 已提交
3218 3219 3220
	if (err)
		goto out_free;

3221 3222 3223 3224 3225 3226 3227 3228 3229
	if (sock->type != SOCK_PACKET) {
		struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;

		/* Original length was stored in sockaddr_ll fields */
		origlen = PACKET_SKB_CB(skb)->sa.origlen;
		sll->sll_family = AF_PACKET;
		sll->sll_protocol = skb->protocol;
	}

3230
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
3231

3232 3233 3234 3235 3236
	if (msg->msg_name) {
		/* If the address length field is there to be filled
		 * in, we fill it in now.
		 */
		if (sock->type == SOCK_PACKET) {
3237
			__sockaddr_check_size(sizeof(struct sockaddr_pkt));
3238 3239 3240
			msg->msg_namelen = sizeof(struct sockaddr_pkt);
		} else {
			struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3241

3242 3243 3244
			msg->msg_namelen = sll->sll_halen +
				offsetof(struct sockaddr_ll, sll_addr);
		}
3245 3246
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
3247
	}
L
Linus Torvalds 已提交
3248

3249
	if (pkt_sk(sk)->auxdata) {
3250 3251 3252 3253 3254
		struct tpacket_auxdata aux;

		aux.tp_status = TP_STATUS_USER;
		if (skb->ip_summed == CHECKSUM_PARTIAL)
			aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3255 3256 3257 3258 3259
		else if (skb->pkt_type != PACKET_OUTGOING &&
			 (skb->ip_summed == CHECKSUM_COMPLETE ||
			  skb_csum_unnecessary(skb)))
			aux.tp_status |= TP_STATUS_CSUM_VALID;

3260
		aux.tp_len = origlen;
3261 3262
		aux.tp_snaplen = skb->len;
		aux.tp_mac = 0;
3263
		aux.tp_net = skb_network_offset(skb);
3264 3265
		if (skb_vlan_tag_present(skb)) {
			aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3266 3267
			aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
			aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3268 3269
		} else {
			aux.tp_vlan_tci = 0;
3270
			aux.tp_vlan_tpid = 0;
3271
		}
3272
		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3273 3274
	}

L
Linus Torvalds 已提交
3275 3276 3277 3278
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
3279
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296

out_free:
	skb_free_datagram(sk, skb);
out:
	return err;
}

static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
			       int *uaddr_len, int peer)
{
	struct net_device *dev;
	struct sock *sk	= sock->sk;

	if (peer)
		return -EOPNOTSUPP;

	uaddr->sa_family = AF_PACKET;
3297
	memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
E
Eric Dumazet 已提交
3298 3299 3300
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
3301
		strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
E
Eric Dumazet 已提交
3302
	rcu_read_unlock();
L
Linus Torvalds 已提交
3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313
	*uaddr_len = sizeof(*uaddr);

	return 0;
}

static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
			  int *uaddr_len, int peer)
{
	struct net_device *dev;
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
3314
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
3315 3316 3317 3318 3319 3320 3321

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
3322
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
3323 3324
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
3325 3326 3327 3328 3329 3330 3331 3332
	if (dev) {
		sll->sll_hatype = dev->type;
		sll->sll_halen = dev->addr_len;
		memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
	} else {
		sll->sll_hatype = 0;	/* Bad: we have no ARPHRD_UNSPEC */
		sll->sll_halen = 0;
	}
E
Eric Dumazet 已提交
3333
	rcu_read_unlock();
3334
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
3335 3336 3337 3338

	return 0;
}

3339 3340
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
3341 3342 3343
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
3344 3345
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
3346
		if (what > 0)
3347
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
3348
		else
3349
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
3350 3351
		break;
	case PACKET_MR_PROMISC:
3352
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
3353
	case PACKET_MR_ALLMULTI:
3354
		return dev_set_allmulti(dev, what);
3355
	case PACKET_MR_UNICAST:
3356 3357
		if (i->alen != dev->addr_len)
			return -EINVAL;
3358
		if (what > 0)
3359
			return dev_uc_add(dev, i->addr);
3360
		else
3361
			return dev_uc_del(dev, i->addr);
3362
		break;
E
Eric Dumazet 已提交
3363 3364
	default:
		break;
L
Linus Torvalds 已提交
3365
	}
3366
	return 0;
L
Linus Torvalds 已提交
3367 3368
}

3369 3370
static void packet_dev_mclist_delete(struct net_device *dev,
				     struct packet_mclist **mlp)
L
Linus Torvalds 已提交
3371
{
3372 3373 3374 3375 3376 3377 3378 3379 3380
	struct packet_mclist *ml;

	while ((ml = *mlp) != NULL) {
		if (ml->ifindex == dev->ifindex) {
			packet_dev_mc(dev, ml, -1);
			*mlp = ml->next;
			kfree(ml);
		} else
			mlp = &ml->next;
L
Linus Torvalds 已提交
3381 3382 3383
	}
}

3384
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
3385 3386 3387 3388 3389 3390 3391 3392 3393
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
3394
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
3395 3396 3397 3398
	if (!dev)
		goto done;

	err = -EINVAL;
3399
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
3400 3401 3402
		goto done;

	err = -ENOBUFS;
3403
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426
	if (i == NULL)
		goto done;

	err = 0;
	for (ml = po->mclist; ml; ml = ml->next) {
		if (ml->ifindex == mreq->mr_ifindex &&
		    ml->type == mreq->mr_type &&
		    ml->alen == mreq->mr_alen &&
		    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
			ml->count++;
			/* Free the new element ... */
			kfree(i);
			goto done;
		}
	}

	i->type = mreq->mr_type;
	i->ifindex = mreq->mr_ifindex;
	i->alen = mreq->mr_alen;
	memcpy(i->addr, mreq->mr_address, i->alen);
	i->count = 1;
	i->next = po->mclist;
	po->mclist = i;
3427 3428 3429 3430 3431
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
3432 3433 3434 3435 3436 3437

done:
	rtnl_unlock();
	return err;
}

3438
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451
{
	struct packet_mclist *ml, **mlp;

	rtnl_lock();

	for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
		if (ml->ifindex == mreq->mr_ifindex &&
		    ml->type == mreq->mr_type &&
		    ml->alen == mreq->mr_alen &&
		    memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
			if (--ml->count == 0) {
				struct net_device *dev;
				*mlp = ml->next;
3452 3453
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
3454 3455 3456
					packet_dev_mc(dev, ml, -1);
				kfree(ml);
			}
3457
			break;
L
Linus Torvalds 已提交
3458 3459 3460
		}
	}
	rtnl_unlock();
3461
	return 0;
L
Linus Torvalds 已提交
3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476
}

static void packet_flush_mclist(struct sock *sk)
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml;

	if (!po->mclist)
		return;

	rtnl_lock();
	while ((ml = po->mclist) != NULL) {
		struct net_device *dev;

		po->mclist = ml->next;
3477 3478
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
3479 3480 3481 3482 3483 3484 3485
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
3486
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
3487 3488
{
	struct sock *sk = sock->sk;
3489
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
3490 3491 3492 3493 3494
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
3495
	switch (optname) {
3496
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
3497 3498
	case PACKET_DROP_MEMBERSHIP:
	{
3499 3500 3501 3502
		struct packet_mreq_max mreq;
		int len = optlen;
		memset(&mreq, 0, sizeof(mreq));
		if (len < sizeof(struct packet_mreq))
L
Linus Torvalds 已提交
3503
			return -EINVAL;
3504 3505
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
3506
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
3507
			return -EFAULT;
3508 3509
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
3510 3511 3512 3513 3514 3515
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
3516

L
Linus Torvalds 已提交
3517
	case PACKET_RX_RING:
J
Johann Baudy 已提交
3518
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
3519
	{
3520 3521
		union tpacket_req_u req_u;
		int len;
L
Linus Torvalds 已提交
3522

3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533
		switch (po->tp_version) {
		case TPACKET_V1:
		case TPACKET_V2:
			len = sizeof(req_u.req);
			break;
		case TPACKET_V3:
		default:
			len = sizeof(req_u.req3);
			break;
		}
		if (optlen < len)
L
Linus Torvalds 已提交
3534
			return -EINVAL;
3535 3536
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
3537
		if (copy_from_user(&req_u.req, optval, len))
L
Linus Torvalds 已提交
3538
			return -EFAULT;
3539 3540
		return packet_set_ring(sk, &req_u, 0,
			optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
3541 3542 3543 3544 3545
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
3546
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
3547
			return -EINVAL;
E
Eric Dumazet 已提交
3548
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
3549 3550 3551 3552 3553
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
3554 3555 3556 3557 3558 3559
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3560
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3561 3562 3563 3564 3565 3566
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
		case TPACKET_V2:
3567
		case TPACKET_V3:
3568 3569 3570 3571 3572 3573
			po->tp_version = val;
			return 0;
		default:
			return -EINVAL;
		}
	}
3574 3575 3576 3577 3578 3579
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3580
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3581 3582 3583 3584 3585 3586
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598 3599
	case PACKET_LOSS:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_loss = !!val;
		return 0;
	}
3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611
	case PACKET_AUXDATA:
	{
		int val;

		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->auxdata = !!val;
		return 0;
	}
3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623
	case PACKET_ORIGDEV:
	{
		int val;

		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->origdev = !!val;
		return 0;
	}
3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639
	case PACKET_VNET_HDR:
	{
		int val;

		if (sock->type != SOCK_RAW)
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (optlen < sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->has_vnet_hdr = !!val;
		return 0;
	}
3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651
	case PACKET_TIMESTAMP:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->tp_tstamp = val;
		return 0;
	}
D
David S. Miller 已提交
3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662
	case PACKET_FANOUT:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		return fanout_add(sk, val & 0xffff, val >> 16);
	}
3663 3664 3665 3666 3667 3668 3669
	case PACKET_FANOUT_DATA:
	{
		if (!po->fanout)
			return -EINVAL;

		return fanout_set_data(po, optval, optlen);
	}
3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682
	case PACKET_TX_HAS_OFF:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_tx_has_off = !!val;
		return 0;
	}
3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694
	case PACKET_QDISC_BYPASS:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;

		po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
		return 0;
	}
L
Linus Torvalds 已提交
3695 3696 3697 3698 3699 3700 3701 3702 3703
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
3704
	int val, lv = sizeof(val);
L
Linus Torvalds 已提交
3705 3706
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
3707
	void *data = &val;
3708
	union tpacket_stats_u st;
W
Willem de Bruijn 已提交
3709
	struct tpacket_rollover_stats rstats;
L
Linus Torvalds 已提交
3710 3711 3712 3713

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

3714 3715
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
3716 3717 3718

	if (len < 0)
		return -EINVAL;
3719

J
Johann Baudy 已提交
3720
	switch (optname) {
L
Linus Torvalds 已提交
3721 3722
	case PACKET_STATISTICS:
		spin_lock_bh(&sk->sk_receive_queue.lock);
3723 3724 3725 3726
		memcpy(&st, &po->stats, sizeof(st));
		memset(&po->stats, 0, sizeof(po->stats));
		spin_unlock_bh(&sk->sk_receive_queue.lock);

3727
		if (po->tp_version == TPACKET_V3) {
3728
			lv = sizeof(struct tpacket_stats_v3);
3729
			st.stats3.tp_packets += st.stats3.tp_drops;
3730
			data = &st.stats3;
3731
		} else {
3732
			lv = sizeof(struct tpacket_stats);
3733
			st.stats1.tp_packets += st.stats1.tp_drops;
3734
			data = &st.stats1;
3735
		}
3736

3737 3738 3739
		break;
	case PACKET_AUXDATA:
		val = po->auxdata;
3740 3741 3742
		break;
	case PACKET_ORIGDEV:
		val = po->origdev;
3743 3744 3745
		break;
	case PACKET_VNET_HDR:
		val = po->has_vnet_hdr;
L
Linus Torvalds 已提交
3746
		break;
3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761
	case PACKET_VERSION:
		val = po->tp_version;
		break;
	case PACKET_HDRLEN:
		if (len > sizeof(int))
			len = sizeof(int);
		if (copy_from_user(&val, optval, len))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
			val = sizeof(struct tpacket_hdr);
			break;
		case TPACKET_V2:
			val = sizeof(struct tpacket2_hdr);
			break;
3762 3763 3764
		case TPACKET_V3:
			val = sizeof(struct tpacket3_hdr);
			break;
3765 3766 3767 3768
		default:
			return -EINVAL;
		}
		break;
3769 3770 3771
	case PACKET_RESERVE:
		val = po->tp_reserve;
		break;
J
Johann Baudy 已提交
3772 3773 3774
	case PACKET_LOSS:
		val = po->tp_loss;
		break;
3775 3776 3777
	case PACKET_TIMESTAMP:
		val = po->tp_tstamp;
		break;
D
David S. Miller 已提交
3778 3779 3780
	case PACKET_FANOUT:
		val = (po->fanout ?
		       ((u32)po->fanout->id |
3781 3782
			((u32)po->fanout->type << 16) |
			((u32)po->fanout->flags << 24)) :
D
David S. Miller 已提交
3783 3784
		       0);
		break;
W
Willem de Bruijn 已提交
3785 3786 3787 3788 3789 3790 3791 3792 3793
	case PACKET_ROLLOVER_STATS:
		if (!po->rollover)
			return -EINVAL;
		rstats.tp_all = atomic_long_read(&po->rollover->num);
		rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
		rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
		data = &rstats;
		lv = sizeof(rstats);
		break;
3794 3795 3796
	case PACKET_TX_HAS_OFF:
		val = po->tp_tx_has_off;
		break;
3797 3798 3799
	case PACKET_QDISC_BYPASS:
		val = packet_use_direct_xmit(po);
		break;
L
Linus Torvalds 已提交
3800 3801 3802 3803
	default:
		return -ENOPROTOOPT;
	}

3804 3805
	if (len > lv)
		len = lv;
3806 3807
	if (put_user(len, optlen))
		return -EFAULT;
3808 3809
	if (copy_to_user(optval, data, len))
		return -EFAULT;
3810
	return 0;
L
Linus Torvalds 已提交
3811 3812 3813
}


3814 3815
static int packet_notifier(struct notifier_block *this,
			   unsigned long msg, void *ptr)
L
Linus Torvalds 已提交
3816 3817
{
	struct sock *sk;
3818
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3819
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
3820

3821
	rcu_read_lock();
3822
	sk_for_each_rcu(sk, &net->packet.sklist) {
L
Linus Torvalds 已提交
3823 3824 3825 3826 3827
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
3828
				packet_dev_mclist_delete(dev, &po->mclist);
3829 3830
			/* fallthrough */

L
Linus Torvalds 已提交
3831 3832 3833 3834
		case NETDEV_DOWN:
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->running) {
3835
					__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
3836 3837 3838 3839 3840
					sk->sk_err = ENETDOWN;
					if (!sock_flag(sk, SOCK_DEAD))
						sk->sk_error_report(sk);
				}
				if (msg == NETDEV_UNREGISTER) {
3841
					packet_cached_dev_reset(po);
L
Linus Torvalds 已提交
3842
					po->ifindex = -1;
3843 3844
					if (po->prot_hook.dev)
						dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
3845 3846 3847 3848 3849 3850
					po->prot_hook.dev = NULL;
				}
				spin_unlock(&po->bind_lock);
			}
			break;
		case NETDEV_UP:
3851 3852
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
3853 3854
				if (po->num)
					register_prot_hook(sk);
3855
				spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
3856 3857 3858 3859
			}
			break;
		}
	}
3860
	rcu_read_unlock();
L
Linus Torvalds 已提交
3861 3862 3863 3864 3865 3866 3867 3868 3869
	return NOTIFY_DONE;
}


static int packet_ioctl(struct socket *sock, unsigned int cmd,
			unsigned long arg)
{
	struct sock *sk = sock->sk;

J
Johann Baudy 已提交
3870
	switch (cmd) {
E
Eric Dumazet 已提交
3871 3872 3873
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
3874

E
Eric Dumazet 已提交
3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892
		return put_user(amount, (int __user *)arg);
	}
	case SIOCINQ:
	{
		struct sk_buff *skb;
		int amount = 0;

		spin_lock_bh(&sk->sk_receive_queue.lock);
		skb = skb_peek(&sk->sk_receive_queue);
		if (skb)
			amount = skb->len;
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		return put_user(amount, (int __user *)arg);
	}
	case SIOCGSTAMP:
		return sock_get_timestamp(sk, (struct timeval __user *)arg);
	case SIOCGSTAMPNS:
		return sock_get_timestampns(sk, (struct timespec __user *)arg);
3893

L
Linus Torvalds 已提交
3894
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909
	case SIOCADDRT:
	case SIOCDELRT:
	case SIOCDARP:
	case SIOCGARP:
	case SIOCSARP:
	case SIOCGIFADDR:
	case SIOCSIFADDR:
	case SIOCGIFBRDADDR:
	case SIOCSIFBRDADDR:
	case SIOCGIFNETMASK:
	case SIOCSIFNETMASK:
	case SIOCGIFDSTADDR:
	case SIOCSIFDSTADDR:
	case SIOCSIFFLAGS:
		return inet_dgram_ops.ioctl(sock, cmd, arg);
L
Linus Torvalds 已提交
3910 3911
#endif

E
Eric Dumazet 已提交
3912 3913
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
3914 3915 3916 3917
	}
	return 0;
}

E
Eric Dumazet 已提交
3918
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
3919 3920 3921 3922 3923 3924 3925
				poll_table *wait)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
	unsigned int mask = datagram_poll(file, sock, wait);

	spin_lock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
3926
	if (po->rx_ring.pg_vec) {
3927 3928
		if (!packet_previous_rx_frame(po, &po->rx_ring,
			TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
3929 3930
			mask |= POLLIN | POLLRDNORM;
	}
3931
	if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
3932
		po->pressure = 0;
L
Linus Torvalds 已提交
3933
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
3934 3935 3936 3937 3938 3939
	spin_lock_bh(&sk->sk_write_queue.lock);
	if (po->tx_ring.pg_vec) {
		if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
			mask |= POLLOUT | POLLWRNORM;
	}
	spin_unlock_bh(&sk->sk_write_queue.lock);
L
Linus Torvalds 已提交
3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950
	return mask;
}


/* Dirty? Well, I still did not learn better way to account
 * for user mmaps.
 */

static void packet_mm_open(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;
E
Eric Dumazet 已提交
3951
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3952
	struct sock *sk = sock->sk;
3953

L
Linus Torvalds 已提交
3954 3955 3956 3957 3958 3959 3960
	if (sk)
		atomic_inc(&pkt_sk(sk)->mapped);
}

static void packet_mm_close(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;
E
Eric Dumazet 已提交
3961
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3962
	struct sock *sk = sock->sk;
3963

L
Linus Torvalds 已提交
3964 3965 3966 3967
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

3968
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
3969 3970
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
3971 3972
};

3973 3974
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
3975 3976 3977
{
	int i;

3978
	for (i = 0; i < len; i++) {
3979
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
3980
			if (is_vmalloc_addr(pg_vec[i].buffer))
3981 3982 3983 3984 3985 3986
				vfree(pg_vec[i].buffer);
			else
				free_pages((unsigned long)pg_vec[i].buffer,
					   order);
			pg_vec[i].buffer = NULL;
		}
L
Linus Torvalds 已提交
3987 3988 3989 3990
	}
	kfree(pg_vec);
}

3991
static char *alloc_one_pg_vec_page(unsigned long order)
3992
{
3993
	char *buffer;
3994 3995 3996 3997 3998 3999 4000
	gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
			  __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;

	buffer = (char *) __get_free_pages(gfp_flags, order);
	if (buffer)
		return buffer;

4001
	/* __get_free_pages failed, fall back to vmalloc */
E
Eric Dumazet 已提交
4002
	buffer = vzalloc((1 << order) * PAGE_SIZE);
4003 4004 4005
	if (buffer)
		return buffer;

4006
	/* vmalloc failed, lets dig into swap here */
4007
	gfp_flags &= ~__GFP_NORETRY;
4008
	buffer = (char *) __get_free_pages(gfp_flags, order);
4009 4010 4011
	if (buffer)
		return buffer;

4012
	/* complete and utter failure */
4013
	return NULL;
4014 4015
}

4016
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4017 4018
{
	unsigned int block_nr = req->tp_block_nr;
4019
	struct pgv *pg_vec;
4020 4021
	int i;

4022
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
4023 4024 4025 4026
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
4027
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4028
		if (unlikely(!pg_vec[i].buffer))
4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039
			goto out_free_pgvec;
	}

out:
	return pg_vec;

out_free_pgvec:
	free_pg_vec(pg_vec, order, block_nr);
	pg_vec = NULL;
	goto out;
}
L
Linus Torvalds 已提交
4040

4041
static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
J
Johann Baudy 已提交
4042
		int closing, int tx_ring)
L
Linus Torvalds 已提交
4043
{
4044
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
4045
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
4046
	int was_running, order = 0;
J
Johann Baudy 已提交
4047 4048
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
4049
	__be16 num;
4050 4051 4052 4053 4054 4055 4056 4057 4058
	int err = -EINVAL;
	/* Added to avoid minimal code churn */
	struct tpacket_req *req = &req_u->req;

	/* Opening a Tx-ring is NOT supported in TPACKET_V3 */
	if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
		WARN(1, "Tx-ring is not supported.\n");
		goto out;
	}
4059

J
Johann Baudy 已提交
4060 4061
	rb = tx_ring ? &po->tx_ring : &po->rx_ring;
	rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
L
Linus Torvalds 已提交
4062

J
Johann Baudy 已提交
4063 4064 4065 4066
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
4067
		if (packet_read_pending(rb))
J
Johann Baudy 已提交
4068 4069
			goto out;
	}
L
Linus Torvalds 已提交
4070

J
Johann Baudy 已提交
4071 4072 4073 4074 4075
	if (req->tp_block_nr) {
		/* Sanity tests and some calculations */
		err = -EBUSY;
		if (unlikely(rb->pg_vec))
			goto out;
L
Linus Torvalds 已提交
4076

4077 4078 4079 4080 4081 4082 4083
		switch (po->tp_version) {
		case TPACKET_V1:
			po->tp_hdrlen = TPACKET_HDRLEN;
			break;
		case TPACKET_V2:
			po->tp_hdrlen = TPACKET2_HDRLEN;
			break;
4084 4085 4086
		case TPACKET_V3:
			po->tp_hdrlen = TPACKET3_HDRLEN;
			break;
4087 4088
		}

J
Johann Baudy 已提交
4089
		err = -EINVAL;
4090
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
4091
			goto out;
4092
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
4093
			goto out;
4094 4095 4096 4097
		if (po->tp_version >= TPACKET_V3 &&
		    (int)(req->tp_block_size -
			  BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
			goto out;
4098
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
4099 4100
					po->tp_reserve))
			goto out;
4101
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
4102
			goto out;
L
Linus Torvalds 已提交
4103

J
Johann Baudy 已提交
4104 4105 4106 4107 4108 4109
		rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
		if (unlikely(rb->frames_per_block <= 0))
			goto out;
		if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
					req->tp_frame_nr))
			goto out;
L
Linus Torvalds 已提交
4110 4111

		err = -ENOMEM;
4112 4113 4114
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
4115
			goto out;
4116 4117 4118 4119 4120 4121
		switch (po->tp_version) {
		case TPACKET_V3:
		/* Transmit path is not supported. We checked
		 * it above but just being paranoid
		 */
			if (!tx_ring)
4122
				init_prb_bdqc(po, rb, pg_vec, req_u);
4123
			break;
4124 4125 4126
		default:
			break;
		}
J
Johann Baudy 已提交
4127 4128 4129 4130
	}
	/* Done */
	else {
		err = -EINVAL;
4131
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
4132
			goto out;
L
Linus Torvalds 已提交
4133 4134 4135 4136 4137 4138 4139 4140 4141 4142
	}

	lock_sock(sk);

	/* Detach socket from network */
	spin_lock(&po->bind_lock);
	was_running = po->running;
	num = po->num;
	if (was_running) {
		po->num = 0;
4143
		__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
4144 4145
	}
	spin_unlock(&po->bind_lock);
4146

L
Linus Torvalds 已提交
4147 4148 4149
	synchronize_net();

	err = -EBUSY;
4150
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
4151 4152
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
4153
		spin_lock_bh(&rb_queue->lock);
4154
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
4155 4156 4157 4158 4159
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

4160 4161
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
4162 4163 4164 4165 4166

		rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
		po->prot_hook.func = (po->rx_ring.pg_vec) ?
						tpacket_rcv : packet_rcv;
		skb_queue_purge(rb_queue);
L
Linus Torvalds 已提交
4167
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
4168 4169
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
4170
	}
4171
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
4172 4173

	spin_lock(&po->bind_lock);
4174
	if (was_running) {
L
Linus Torvalds 已提交
4175
		po->num = num;
4176
		register_prot_hook(sk);
L
Linus Torvalds 已提交
4177 4178
	}
	spin_unlock(&po->bind_lock);
4179 4180 4181
	if (closing && (po->tp_version > TPACKET_V2)) {
		/* Because we don't support block-based V3 on tx-ring */
		if (!tx_ring)
4182
			prb_shutdown_retire_blk_timer(po, rb_queue);
4183
	}
L
Linus Torvalds 已提交
4184 4185 4186 4187 4188 4189 4190 4191
	release_sock(sk);

	if (pg_vec)
		free_pg_vec(pg_vec, order, req->tp_block_nr);
out:
	return err;
}

J
Johann Baudy 已提交
4192 4193
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
4194 4195 4196
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
4197 4198
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
4199 4200 4201 4202 4203 4204 4205
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

4206
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217

	expected_size = 0;
	for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
		if (rb->pg_vec) {
			expected_size += rb->pg_vec_len
						* rb->pg_vec_pages
						* PAGE_SIZE;
		}
	}

	if (expected_size == 0)
L
Linus Torvalds 已提交
4218
		goto out;
J
Johann Baudy 已提交
4219 4220 4221

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
4222 4223 4224
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
4225 4226 4227 4228 4229
	for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
		if (rb->pg_vec == NULL)
			continue;

		for (i = 0; i < rb->pg_vec_len; i++) {
4230 4231
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
4232 4233
			int pg_num;

C
Changli Gao 已提交
4234 4235
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
4236 4237 4238 4239
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
4240
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
4241
			}
4242
		}
L
Linus Torvalds 已提交
4243
	}
J
Johann Baudy 已提交
4244

4245
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
4246 4247 4248 4249
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
4250
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
4251 4252 4253
	return err;
}

4254
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind_spkt,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
	.getname =	packet_getname_spkt,
	.poll =		datagram_poll,
	.ioctl =	packet_ioctl,
	.listen =	sock_no_listen,
	.shutdown =	sock_no_shutdown,
	.setsockopt =	sock_no_setsockopt,
	.getsockopt =	sock_no_getsockopt,
	.sendmsg =	packet_sendmsg_spkt,
	.recvmsg =	packet_recvmsg,
	.mmap =		sock_no_mmap,
	.sendpage =	sock_no_sendpage,
};

4275
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
4276 4277 4278 4279 4280 4281 4282
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
4283
	.getname =	packet_getname,
L
Linus Torvalds 已提交
4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295
	.poll =		packet_poll,
	.ioctl =	packet_ioctl,
	.listen =	sock_no_listen,
	.shutdown =	sock_no_shutdown,
	.setsockopt =	packet_setsockopt,
	.getsockopt =	packet_getsockopt,
	.sendmsg =	packet_sendmsg,
	.recvmsg =	packet_recvmsg,
	.mmap =		packet_mmap,
	.sendpage =	sock_no_sendpage,
};

4296
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
4297 4298 4299 4300 4301 4302
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
4303
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
4304 4305 4306 4307 4308
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4309
	__acquires(RCU)
L
Linus Torvalds 已提交
4310
{
4311
	struct net *net = seq_file_net(seq);
4312 4313 4314

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
4315 4316 4317 4318
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
4319
	struct net *net = seq_file_net(seq);
4320
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
4321 4322 4323
}

static void packet_seq_stop(struct seq_file *seq, void *v)
4324
	__releases(RCU)
L
Linus Torvalds 已提交
4325
{
4326
	rcu_read_unlock();
L
Linus Torvalds 已提交
4327 4328
}

4329
static int packet_seq_show(struct seq_file *seq, void *v)
L
Linus Torvalds 已提交
4330 4331 4332 4333
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
4334
		struct sock *s = sk_entry(v);
L
Linus Torvalds 已提交
4335 4336 4337
		const struct packet_sock *po = pkt_sk(s);

		seq_printf(seq,
D
Dan Rosenberg 已提交
4338
			   "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
L
Linus Torvalds 已提交
4339 4340 4341 4342 4343 4344 4345
			   s,
			   atomic_read(&s->sk_refcnt),
			   s->sk_type,
			   ntohs(po->num),
			   po->ifindex,
			   po->running,
			   atomic_read(&s->sk_rmem_alloc),
4346
			   from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
E
Eric Dumazet 已提交
4347
			   sock_i_ino(s));
L
Linus Torvalds 已提交
4348 4349 4350 4351 4352
	}

	return 0;
}

4353
static const struct seq_operations packet_seq_ops = {
L
Linus Torvalds 已提交
4354 4355 4356 4357 4358 4359 4360 4361
	.start	= packet_seq_start,
	.next	= packet_seq_next,
	.stop	= packet_seq_stop,
	.show	= packet_seq_show,
};

static int packet_seq_open(struct inode *inode, struct file *file)
{
4362 4363
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
4364 4365
}

4366
static const struct file_operations packet_seq_fops = {
L
Linus Torvalds 已提交
4367 4368 4369 4370
	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
4371
	.release	= seq_release_net,
L
Linus Torvalds 已提交
4372 4373 4374 4375
};

#endif

4376
static int __net_init packet_net_init(struct net *net)
4377
{
4378
	mutex_init(&net->packet.sklist_lock);
4379
	INIT_HLIST_HEAD(&net->packet.sklist);
4380

4381
	if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4382 4383 4384 4385 4386
		return -ENOMEM;

	return 0;
}

4387
static void __net_exit packet_net_exit(struct net *net)
4388
{
4389
	remove_proc_entry("packet", net->proc_net);
4390 4391 4392 4393 4394 4395 4396 4397
}

static struct pernet_operations packet_net_ops = {
	.init = packet_net_init,
	.exit = packet_net_exit,
};


L
Linus Torvalds 已提交
4398 4399 4400
static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
4401
	unregister_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413
	sock_unregister(PF_PACKET);
	proto_unregister(&packet_proto);
}

static int __init packet_init(void)
{
	int rc = proto_register(&packet_proto, 0);

	if (rc != 0)
		goto out;

	sock_register(&packet_family_ops);
4414
	register_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
4415 4416 4417 4418 4419 4420 4421 4422 4423
	register_netdevice_notifier(&packet_netdev_notifier);
out:
	return rc;
}

module_init(packet_init);
module_exit(packet_exit);
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_PACKET);