af_packet.c 61.2 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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 *
 *		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/system.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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#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif

/*
   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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struct packet_mclist {
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	struct packet_mclist	*next;
	int			ifindex;
	int			count;
	unsigned short		type;
	unsigned short		alen;
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	unsigned char		addr[MAX_ADDR_LEN];
};
/* 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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static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
		int closing, int tx_ring);

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#define PGV_FROM_VMALLOC 1
struct pgv {
	char *buffer;
};

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struct packet_ring_buffer {
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	struct pgv		*pg_vec;
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	unsigned int		head;
	unsigned int		frames_per_block;
	unsigned int		frame_size;
	unsigned int		frame_max;

	unsigned int		pg_vec_order;
	unsigned int		pg_vec_pages;
	unsigned int		pg_vec_len;

	atomic_t		pending;
};

struct packet_sock;
static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
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static void packet_flush_mclist(struct sock *sk);

struct packet_sock {
	/* struct sock has to be the first member of packet_sock */
	struct sock		sk;
	struct tpacket_stats	stats;
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	struct packet_ring_buffer	rx_ring;
	struct packet_ring_buffer	tx_ring;
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	int			copy_thresh;
	spinlock_t		bind_lock;
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	struct mutex		pg_vec_lock;
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	unsigned int		running:1,	/* prot_hook is attached*/
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				auxdata:1,
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				origdev:1,
				has_vnet_hdr:1;
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	int			ifindex;	/* bound device		*/
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	__be16			num;
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	struct packet_mclist	*mclist;
	atomic_t		mapped;
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	enum tpacket_versions	tp_version;
	unsigned int		tp_hdrlen;
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	unsigned int		tp_reserve;
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	unsigned int		tp_loss:1;
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	unsigned int		tp_tstamp;
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	struct packet_type	prot_hook ____cacheline_aligned_in_smp;
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};

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struct packet_skb_cb {
	unsigned int origlen;
	union {
		struct sockaddr_pkt pkt;
		struct sockaddr_ll ll;
	} sa;
};

#define PACKET_SKB_CB(__skb)	((struct packet_skb_cb *)((__skb)->cb))
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static inline __pure struct page *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 {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} 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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	default:
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		pr_err("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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{
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} 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;
	default:
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		pr_err("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 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;
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;

	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;
}

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

static inline void *packet_previous_frame(struct packet_sock *po,
		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);
}

static inline void packet_increment_head(struct packet_ring_buffer *buff)
{
	buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}

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static inline struct packet_sock *pkt_sk(struct sock *sk)
{
	return (struct packet_sock *)sk;
}

static void packet_sock_destruct(struct sock *sk)
{
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	skb_queue_purge(&sk->sk_error_queue);

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	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
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	if (!sock_flag(sk, SOCK_DEAD)) {
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		pr_err("Attempt to release alive packet socket: %p\n", sk);
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		return;
	}

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	sk_refcnt_debug_dec(sk);
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}


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static const struct proto_ops packet_ops;
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static const struct proto_ops packet_ops_spkt;
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static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
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{
	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;
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	/*
	 *	Yank back the headers [hope the device set this
	 *	right or kerboom...]
	 *
	 *	Incoming packets have ll header pulled,
	 *	push it back.
	 *
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	 *	For outgoing ones skb->data == skb_mac_header(skb)
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	 *	so that this procedure is noop.
	 */

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

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	if (!net_eq(dev_net(dev), sock_net(sk)))
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		goto out;

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	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL)
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		goto oom;

	/* drop any routing info */
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	skb_dst_drop(skb);
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	/* drop conntrack reference */
	nf_reset(skb);

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	spkt = &PACKET_SKB_CB(skb)->sa.pkt;
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	skb_push(skb, skb->data - skb_mac_header(skb));
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	/*
	 *	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.
	 */

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	if (sock_queue_rcv_skb(sk, skb) == 0)
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		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
 */
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static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
			       struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
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	struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
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	struct sk_buff *skb = NULL;
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	struct net_device *dev;
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	__be16 proto = 0;
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	int err;
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	/*
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	 *	Get and verify the address.
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	 */

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	if (saddr) {
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		if (msg->msg_namelen < sizeof(struct sockaddr))
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			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 */
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	/*
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	 *	Find the device first to size check it
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	 */

	saddr->spkt_device[13] = 0;
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retry:
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	rcu_read_lock();
	dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
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	err = -ENODEV;
	if (dev == NULL)
		goto out_unlock;
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	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

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	/*
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	 * 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.
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	 */
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	err = -EMSGSIZE;
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	if (len > dev->mtu + dev->hard_header_len)
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		goto out_unlock;

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	if (!skb) {
		size_t reserved = LL_RESERVED_SPACE(dev);
		unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;

		rcu_read_unlock();
		skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
		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);
		}
		err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
		if (err)
			goto out_free;
		goto retry;
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	}

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	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
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	skb->mark = sk->sk_mark;
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	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
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	if (err < 0)
		goto out_unlock;
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	dev_queue_xmit(skb);
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	rcu_read_unlock();
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	return len;
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out_unlock:
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	rcu_read_unlock();
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out_free:
	kfree_skb(skb);
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	return err;
}

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static inline unsigned int run_filter(const struct sk_buff *skb,
				      const struct sock *sk,
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				      unsigned int res)
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{
	struct sk_filter *filter;
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	rcu_read_lock_bh();
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	filter = rcu_dereference_bh(sk->sk_filter);
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	if (filter != NULL)
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		res = sk_run_filter(skb, filter->insns);
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	rcu_read_unlock_bh();
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	return res;
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}

/*
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 * 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.
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 */

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static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
		      struct packet_type *pt, struct net_device *orig_dev)
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{
	struct sock *sk;
	struct sockaddr_ll *sll;
	struct packet_sock *po;
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	u8 *skb_head = skb->data;
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	int skb_len = skb->len;
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	unsigned int snaplen, res;
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	if (skb->pkt_type == PACKET_LOOPBACK)
		goto drop;

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

O
Octavian Purdila 已提交
563
	if (!net_eq(dev_net(dev), sock_net(sk)))
564 565
		goto drop;

L
Linus Torvalds 已提交
566 567
	skb->dev = dev;

568
	if (dev->header_ops) {
L
Linus Torvalds 已提交
569
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
570 571 572 573 574
		 * 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
575 576
		 */
		if (sk->sk_type != SOCK_DGRAM)
577
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
578 579
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
580
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
581 582 583 584 585
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
586 587
	res = run_filter(skb, sk, snaplen);
	if (!res)
588
		goto drop_n_restore;
D
David S. Miller 已提交
589 590
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608

	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
	    (unsigned)sk->sk_rcvbuf)
		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;
		}
		kfree_skb(skb);
		skb = nskb;
	}

609 610 611 612
	BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
		     sizeof(skb->cb));

	sll = &PACKET_SKB_CB(skb)->sa.ll;
L
Linus Torvalds 已提交
613 614 615 616
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
617
	if (unlikely(po->origdev))
618 619 620
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
621

S
Stephen Hemminger 已提交
622
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
623

624
	PACKET_SKB_CB(skb)->origlen = skb->len;
625

L
Linus Torvalds 已提交
626 627 628 629 630
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
631
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
632

633 634 635
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
636 637
	spin_lock(&sk->sk_receive_queue.lock);
	po->stats.tp_packets++;
638
	skb->dropcount = atomic_read(&sk->sk_drops);
L
Linus Torvalds 已提交
639 640 641 642 643 644
	__skb_queue_tail(&sk->sk_receive_queue, skb);
	spin_unlock(&sk->sk_receive_queue.lock);
	sk->sk_data_ready(sk, skb->len);
	return 0;

drop_n_acct:
645
	po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
L
Linus Torvalds 已提交
646 647 648 649 650 651 652

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
653
	consume_skb(skb);
L
Linus Torvalds 已提交
654 655 656
	return 0;
}

E
Eric Dumazet 已提交
657 658
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
659 660 661 662
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
663 664 665 666 667
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;
E
Eric Dumazet 已提交
668
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
669
	int skb_len = skb->len;
D
David S. Miller 已提交
670
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
671
	unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
672
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
673
	struct sk_buff *copy_skb = NULL;
674
	struct timeval tv;
675
	struct timespec ts;
676
	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
L
Linus Torvalds 已提交
677 678 679 680 681 682 683

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

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

O
Octavian Purdila 已提交
684
	if (!net_eq(dev_net(dev), sock_net(sk)))
685 686
		goto drop;

687
	if (dev->header_ops) {
L
Linus Torvalds 已提交
688
		if (sk->sk_type != SOCK_DGRAM)
689
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
690 691
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
692
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
693 694 695
		}
	}

696 697 698
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;

L
Linus Torvalds 已提交
699 700
	snaplen = skb->len;

D
David S. Miller 已提交
701 702
	res = run_filter(skb, sk, snaplen);
	if (!res)
703
		goto drop_n_restore;
D
David S. Miller 已提交
704 705
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
706 707

	if (sk->sk_type == SOCK_DGRAM) {
708 709
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
710
	} else {
711
		unsigned maclen = skb_network_offset(skb);
712
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
713 714
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
715 716 717
		macoff = netoff - maclen;
	}

J
Johann Baudy 已提交
718
	if (macoff + snaplen > po->rx_ring.frame_size) {
L
Linus Torvalds 已提交
719 720 721 722 723 724 725 726 727 728 729 730
		if (po->copy_thresh &&
		    atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
		    (unsigned)sk->sk_rcvbuf) {
			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);
		}
J
Johann Baudy 已提交
731
		snaplen = po->rx_ring.frame_size - macoff;
L
Linus Torvalds 已提交
732 733 734 735 736
		if ((int)snaplen < 0)
			snaplen = 0;
	}

	spin_lock(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
737
	h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
738
	if (!h.raw)
L
Linus Torvalds 已提交
739
		goto ring_is_full;
J
Johann Baudy 已提交
740
	packet_increment_head(&po->rx_ring);
L
Linus Torvalds 已提交
741 742 743 744 745 746 747 748 749
	po->stats.tp_packets++;
	if (copy_skb) {
		status |= TP_STATUS_COPY;
		__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
	}
	if (!po->stats.tp_drops)
		status &= ~TP_STATUS_LOSING;
	spin_unlock(&sk->sk_receive_queue.lock);

750
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
L
Linus Torvalds 已提交
751

752 753 754 755 756 757
	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;
758 759 760 761 762 763 764
		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
				&& shhwtstamps->syststamp.tv64)
			tv = ktime_to_timeval(shhwtstamps->syststamp);
		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
				&& shhwtstamps->hwtstamp.tv64)
			tv = ktime_to_timeval(shhwtstamps->hwtstamp);
		else if (skb->tstamp.tv64)
765 766 767 768 769 770 771 772 773 774 775 776
			tv = ktime_to_timeval(skb->tstamp);
		else
			do_gettimeofday(&tv);
		h.h1->tp_sec = tv.tv_sec;
		h.h1->tp_usec = tv.tv_usec;
		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;
777 778 779 780 781 782 783
		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
				&& shhwtstamps->syststamp.tv64)
			ts = ktime_to_timespec(shhwtstamps->syststamp);
		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
				&& shhwtstamps->hwtstamp.tv64)
			ts = ktime_to_timespec(shhwtstamps->hwtstamp);
		else if (skb->tstamp.tv64)
784 785 786 787 788
			ts = ktime_to_timespec(skb->tstamp);
		else
			getnstimeofday(&ts);
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
E
Eric Dumazet 已提交
789
		h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
790 791 792 793 794
		hdrlen = sizeof(*h.h2);
		break;
	default:
		BUG();
	}
L
Linus Torvalds 已提交
795

796
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
797
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
798 799 800 801
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
802
	if (unlikely(po->origdev))
803 804 805
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
806

807
	__packet_set_status(po, h.raw, status);
R
Ralf Baechle 已提交
808
	smp_mb();
809
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
L
Linus Torvalds 已提交
810
	{
811 812 813 814 815
		u8 *start, *end;

		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
816
	}
817
#endif
L
Linus Torvalds 已提交
818 819 820 821 822 823 824 825 826

	sk->sk_data_ready(sk, 0);

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
827
	kfree_skb(skb);
L
Linus Torvalds 已提交
828 829 830 831 832 833 834
	return 0;

ring_is_full:
	po->stats.tp_drops++;
	spin_unlock(&sk->sk_receive_queue.lock);

	sk->sk_data_ready(sk, 0);
835
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
836 837 838
	goto drop_n_restore;
}

J
Johann Baudy 已提交
839 840 841
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
E
Eric Dumazet 已提交
842
	void *ph;
L
Linus Torvalds 已提交
843

J
Johann Baudy 已提交
844
	BUG_ON(skb == NULL);
L
Linus Torvalds 已提交
845

J
Johann Baudy 已提交
846 847 848 849 850 851 852 853 854 855 856
	if (likely(po->tx_ring.pg_vec)) {
		ph = skb_shinfo(skb)->destructor_arg;
		BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
		BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
		atomic_dec(&po->tx_ring.pending);
		__packet_set_status(po, ph, TP_STATUS_AVAILABLE);
	}

	sock_wfree(skb);
}

E
Eric Dumazet 已提交
857 858 859
static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
		void *frame, struct net_device *dev, int size_max,
		__be16 proto, unsigned char *addr)
J
Johann Baudy 已提交
860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876
{
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} ph;
	int to_write, offset, len, tp_len, nr_frags, len_max;
	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;
877
	skb->mark = po->sk.sk_mark;
J
Johann Baudy 已提交
878 879 880 881 882 883 884 885 886 887 888
	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;
	}
	if (unlikely(tp_len > size_max)) {
E
Eric Dumazet 已提交
889
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
J
Johann Baudy 已提交
890 891 892 893 894 895 896 897 898 899 900 901 902 903
		return -EMSGSIZE;
	}

	skb_reserve(skb, LL_RESERVED_SPACE(dev));
	skb_reset_network_header(skb);

	data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
	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
904
	} else if (dev->hard_header_len) {
J
Johann Baudy 已提交
905 906
		/* net device doesn't like empty head */
		if (unlikely(tp_len <= dev->hard_header_len)) {
E
Eric Dumazet 已提交
907 908
			pr_err("packet size is too short (%d < %d)\n",
			       tp_len, dev->hard_header_len);
J
Johann Baudy 已提交
909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935
			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;
	}

	err = -EFAULT;
	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
936 937
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
938 939 940
			return -EFAULT;
		}

941 942
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
943 944
		flush_dcache_page(page);
		get_page(page);
945
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961
		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 socket *sock;
	struct sk_buff *skb;
	struct net_device *dev;
	__be16 proto;
	int ifindex, err, reserve = 0;
E
Eric Dumazet 已提交
962 963
	void *ph;
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
J
Johann Baudy 已提交
964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
	int status = 0;

	sock = po->sk.sk_socket;

	mutex_lock(&po->pg_vec_lock);

	err = -EBUSY;
	if (saddr == NULL) {
		ifindex	= po->ifindex;
		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;
		ifindex	= saddr->sll_ifindex;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
	}

	dev = dev_get_by_index(sock_net(&po->sk), ifindex);
	err = -ENXIO;
	if (unlikely(dev == NULL))
		goto out;

	reserve = dev->hard_header_len;

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

	size_max = po->tx_ring.frame_size
1003
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048

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

	do {
		ph = packet_current_frame(po, &po->tx_ring,
				TP_STATUS_SEND_REQUEST);

		if (unlikely(ph == NULL)) {
			schedule();
			continue;
		}

		status = TP_STATUS_SEND_REQUEST;
		skb = sock_alloc_send_skb(&po->sk,
				LL_ALLOCATED_SPACE(dev)
				+ sizeof(struct sockaddr_ll),
				0, &err);

		if (unlikely(skb == NULL))
			goto out_status;

		tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
				addr);

		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;
			}
		}

		skb->destructor = tpacket_destruct_skb;
		__packet_set_status(po, ph, TP_STATUS_SENDING);
		atomic_inc(&po->tx_ring.pending);

		status = TP_STATUS_SEND_REQUEST;
		err = dev_queue_xmit(skb);
1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062
		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
1063 1064
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
1065 1066 1067 1068
	} while (likely((ph != NULL) ||
			((!(msg->msg_flags & MSG_DONTWAIT)) &&
			 (atomic_read(&po->tx_ring.pending))))
		);
J
Johann Baudy 已提交
1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082

	err = len_sum;
	goto out_put;

out_status:
	__packet_set_status(po, ph, status);
	kfree_skb(skb);
out_put:
	dev_put(dev);
out:
	mutex_unlock(&po->pg_vec_lock);
	return err;
}

1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106
static inline 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)
{
	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,
				   err);
	if (!skb)
		return NULL;

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

	return skb;
}

J
Johann Baudy 已提交
1107
static int packet_snd(struct socket *sock,
L
Linus Torvalds 已提交
1108 1109 1110
			  struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
1111
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
L
Linus Torvalds 已提交
1112 1113
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
1114
	__be16 proto;
L
Linus Torvalds 已提交
1115 1116
	unsigned char *addr;
	int ifindex, err, reserve = 0;
1117 1118 1119 1120 1121
	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;
L
Linus Torvalds 已提交
1122 1123

	/*
1124
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1125
	 */
1126

L
Linus Torvalds 已提交
1127 1128 1129 1130 1131 1132 1133 1134
	if (saddr == NULL) {
		ifindex	= po->ifindex;
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
1135 1136
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142
		ifindex	= saddr->sll_ifindex;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
	}


1143
	dev = dev_get_by_index(sock_net(sk), ifindex);
L
Linus Torvalds 已提交
1144 1145 1146 1147 1148 1149
	err = -ENXIO;
	if (dev == NULL)
		goto out_unlock;
	if (sock->type == SOCK_RAW)
		reserve = dev->hard_header_len;

1150 1151 1152 1153
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201
	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;

		err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
				       vnet_hdr_len);
		if (err < 0)
			goto out_unlock;

		if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
		    (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
		      vnet_hdr.hdr_len))
			vnet_hdr.hdr_len = vnet_hdr.csum_start +
						 vnet_hdr.csum_offset + 2;

		err = -EINVAL;
		if (vnet_hdr.hdr_len > len)
			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;

		}
	}

L
Linus Torvalds 已提交
1202
	err = -EMSGSIZE;
1203
	if (!gso_type && (len > dev->mtu+reserve))
L
Linus Torvalds 已提交
1204 1205
		goto out_unlock;

1206 1207 1208 1209
	err = -ENOBUFS;
	skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
			       LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
			       msg->msg_flags & MSG_DONTWAIT, &err);
E
Eric Dumazet 已提交
1210
	if (skb == NULL)
L
Linus Torvalds 已提交
1211 1212
		goto out_unlock;

1213
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
1214

1215 1216
	err = -EINVAL;
	if (sock->type == SOCK_DGRAM &&
1217
	    (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1218
		goto out_free;
L
Linus Torvalds 已提交
1219 1220

	/* Returns -EFAULT on error */
1221
	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
L
Linus Torvalds 已提交
1222 1223
	if (err)
		goto out_free;
1224
	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1225 1226
	if (err < 0)
		goto out_free;
L
Linus Torvalds 已提交
1227 1228 1229 1230

	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1231
	skb->mark = sk->sk_mark;
L
Linus Torvalds 已提交
1232

1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251
	if (po->has_vnet_hdr) {
		if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
			if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
						  vnet_hdr.csum_offset)) {
				err = -EINVAL;
				goto out_free;
			}
		}

		skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
		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;
	}

L
Linus Torvalds 已提交
1252 1253 1254 1255 1256 1257 1258 1259 1260 1261
	/*
	 *	Now send it
	 */

	err = dev_queue_xmit(skb);
	if (err > 0 && (err = net_xmit_errno(err)) != 0)
		goto out_unlock;

	dev_put(dev);

E
Eric Dumazet 已提交
1262
	return len;
L
Linus Torvalds 已提交
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272

out_free:
	kfree_skb(skb);
out_unlock:
	if (dev)
		dev_put(dev);
out:
	return err;
}

J
Johann Baudy 已提交
1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283
static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
		struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
	if (po->tx_ring.pg_vec)
		return tpacket_snd(po, msg);
	else
		return packet_snd(sock, msg, len);
}

L
Linus Torvalds 已提交
1284 1285 1286 1287 1288 1289 1290 1291 1292
/*
 *	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;
1293
	struct net *net;
J
Johann Baudy 已提交
1294
	struct tpacket_req req;
L
Linus Torvalds 已提交
1295 1296 1297 1298

	if (!sk)
		return 0;

1299
	net = sock_net(sk);
L
Linus Torvalds 已提交
1300 1301
	po = pkt_sk(sk);

1302 1303
	spin_lock_bh(&net->packet.sklist_lock);
	sk_del_node_init_rcu(sk);
1304
	sock_prot_inuse_add(net, sk->sk_prot, -1);
1305
	spin_unlock_bh(&net->packet.sklist_lock);
L
Linus Torvalds 已提交
1306

1307
	spin_lock(&po->bind_lock);
L
Linus Torvalds 已提交
1308 1309
	if (po->running) {
		/*
1310
		 * Remove from protocol table
L
Linus Torvalds 已提交
1311 1312 1313
		 */
		po->running = 0;
		po->num = 0;
1314
		__dev_remove_pack(&po->prot_hook);
L
Linus Torvalds 已提交
1315 1316
		__sock_put(sk);
	}
1317
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
1318 1319 1320

	packet_flush_mclist(sk);

J
Johann Baudy 已提交
1321 1322 1323 1324 1325 1326 1327
	memset(&req, 0, sizeof(req));

	if (po->rx_ring.pg_vec)
		packet_set_ring(sk, &req, 1, 0);

	if (po->tx_ring.pg_vec)
		packet_set_ring(sk, &req, 1, 1);
L
Linus Torvalds 已提交
1328

1329
	synchronize_net();
L
Linus Torvalds 已提交
1330 1331 1332 1333 1334 1335 1336 1337 1338
	/*
	 *	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);
1339
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
1340 1341 1342 1343 1344 1345 1346 1347 1348

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

A
Al Viro 已提交
1349
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
L
Linus Torvalds 已提交
1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376
{
	struct packet_sock *po = pkt_sk(sk);
	/*
	 *	Detach an existing hook if present.
	 */

	lock_sock(sk);

	spin_lock(&po->bind_lock);
	if (po->running) {
		__sock_put(sk);
		po->running = 0;
		po->num = 0;
		spin_unlock(&po->bind_lock);
		dev_remove_pack(&po->prot_hook);
		spin_lock(&po->bind_lock);
	}

	po->num = protocol;
	po->prot_hook.type = protocol;
	po->prot_hook.dev = dev;

	po->ifindex = dev ? dev->ifindex : 0;

	if (protocol == 0)
		goto out_unlock;

1377
	if (!dev || (dev->flags & IFF_UP)) {
L
Linus Torvalds 已提交
1378 1379 1380
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
1381 1382 1383 1384
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396
	}

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
1397 1398
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
1399
{
E
Eric Dumazet 已提交
1400
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1401 1402 1403
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
1404

L
Linus Torvalds 已提交
1405 1406 1407
	/*
	 *	Check legality
	 */
1408

1409
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
1410
		return -EINVAL;
E
Eric Dumazet 已提交
1411
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
1412

1413
	dev = dev_get_by_name(sock_net(sk), name);
L
Linus Torvalds 已提交
1414 1415 1416 1417 1418 1419 1420 1421 1422
	if (dev) {
		err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
		dev_put(dev);
	}
	return err;
}

static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
E
Eric Dumazet 已提交
1423 1424
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1425 1426 1427 1428 1429 1430 1431
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
1432

L
Linus Torvalds 已提交
1433 1434 1435 1436 1437 1438 1439
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
1440
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458
		if (dev == NULL)
			goto out;
	}
	err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
	if (dev)
		dev_put(dev);

out:
	return err;
}

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

/*
1459
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
1460 1461
 */

1462 1463
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
1464 1465 1466
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
1467
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
1468 1469 1470 1471
	int err;

	if (!capable(CAP_NET_RAW))
		return -EPERM;
1472 1473
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
1474 1475 1476 1477 1478
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
1479
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
L
Linus Torvalds 已提交
1480 1481 1482 1483 1484 1485
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
1486

L
Linus Torvalds 已提交
1487 1488 1489 1490
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
1491
	po->num = proto;
L
Linus Torvalds 已提交
1492 1493

	sk->sk_destruct = packet_sock_destruct;
1494
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
1495 1496 1497 1498 1499 1500

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
1501
	mutex_init(&po->pg_vec_lock);
L
Linus Torvalds 已提交
1502
	po->prot_hook.func = packet_rcv;
1503

L
Linus Torvalds 已提交
1504 1505
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
1506

L
Linus Torvalds 已提交
1507 1508
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
1509 1510
	if (proto) {
		po->prot_hook.type = proto;
L
Linus Torvalds 已提交
1511 1512 1513 1514 1515
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
	}

1516 1517
	spin_lock_bh(&net->packet.sklist_lock);
	sk_add_node_rcu(sk, &net->packet.sklist);
1518
	sock_prot_inuse_add(net, &packet_proto, 1);
1519 1520
	spin_unlock_bh(&net->packet.sklist_lock);

E
Eric Dumazet 已提交
1521
	return 0;
L
Linus Torvalds 已提交
1522 1523 1524 1525
out:
	return err;
}

1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 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 1570
static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
{
	struct sock_exterr_skb *serr;
	struct sk_buff *skb, *skb2;
	int copied, err;

	err = -EAGAIN;
	skb = skb_dequeue(&sk->sk_error_queue);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	serr = SKB_EXT_ERR(skb);
	put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
		 sizeof(serr->ee), &serr->ee);

	msg->msg_flags |= MSG_ERRQUEUE;
	err = copied;

	/* Reset and regenerate socket error */
	spin_lock_bh(&sk->sk_error_queue.lock);
	sk->sk_err = 0;
	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
		spin_unlock_bh(&sk->sk_error_queue.lock);
		sk->sk_error_report(sk);
	} else
		spin_unlock_bh(&sk->sk_error_queue.lock);

out_free_skb:
	kfree_skb(skb);
out:
	return err;
}

L
Linus Torvalds 已提交
1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581
/*
 *	Pull a packet from our receive queue and hand it to the user.
 *	If necessary we block.
 */

static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
			  struct msghdr *msg, size_t len, int flags)
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	int copied, err;
1582
	struct sockaddr_ll *sll;
1583
	int vnet_hdr_len = 0;
L
Linus Torvalds 已提交
1584 1585

	err = -EINVAL;
1586
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
1587 1588 1589 1590 1591 1592 1593 1594
		goto out;

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

1595 1596 1597 1598 1599
	if (flags & MSG_ERRQUEUE) {
		err = packet_recv_error(sk, msg, len);
		goto out;
	}

L
Linus Torvalds 已提交
1600 1601 1602 1603 1604 1605 1606 1607 1608
	/*
	 *	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
1609
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
1610 1611

	/*
1612
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
1613 1614 1615 1616
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

1617
	if (skb == NULL)
L
Linus Torvalds 已提交
1618 1619
		goto out;

1620 1621 1622 1623 1624
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
1625
		if (len < vnet_hdr_len)
1626 1627
			goto out_free;

1628 1629
		len -= vnet_hdr_len;

1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663
		if (skb_is_gso(skb)) {
			struct skb_shared_info *sinfo = skb_shinfo(skb);

			/* This is a hint as to how much should be linear. */
			vnet_hdr.hdr_len = skb_headlen(skb);
			vnet_hdr.gso_size = sinfo->gso_size;
			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;
			vnet_hdr.csum_start = skb->csum_start -
							skb_headroom(skb);
			vnet_hdr.csum_offset = skb->csum_offset;
		} /* else everything is zero */

		err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
				     vnet_hdr_len);
		if (err < 0)
			goto out_free;
	}

1664 1665 1666 1667 1668
	/*
	 *	If the address length field is there to be filled in, we fill
	 *	it in now.
	 */

1669
	sll = &PACKET_SKB_CB(skb)->sa.ll;
1670 1671 1672 1673 1674
	if (sock->type == SOCK_PACKET)
		msg->msg_namelen = sizeof(struct sockaddr_pkt);
	else
		msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);

L
Linus Torvalds 已提交
1675 1676 1677 1678 1679 1680
	/*
	 *	You lose any data beyond the buffer you gave. If it worries a
	 *	user program they can ask the device for its MTU anyway.
	 */

	copied = skb->len;
E
Eric Dumazet 已提交
1681 1682 1683
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
1684 1685 1686 1687 1688 1689
	}

	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free;

1690
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
1691 1692

	if (msg->msg_name)
1693 1694
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
L
Linus Torvalds 已提交
1695

1696
	if (pkt_sk(sk)->auxdata) {
1697 1698 1699 1700 1701 1702 1703 1704
		struct tpacket_auxdata aux;

		aux.tp_status = TP_STATUS_USER;
		if (skb->ip_summed == CHECKSUM_PARTIAL)
			aux.tp_status |= TP_STATUS_CSUMNOTREADY;
		aux.tp_len = PACKET_SKB_CB(skb)->origlen;
		aux.tp_snaplen = skb->len;
		aux.tp_mac = 0;
1705
		aux.tp_net = skb_network_offset(skb);
E
Eric Dumazet 已提交
1706
		aux.tp_vlan_tci = vlan_tx_tag_get(skb);
1707 1708

		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1709 1710
	}

L
Linus Torvalds 已提交
1711 1712 1713 1714
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
1715
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732

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;
E
Eric Dumazet 已提交
1733 1734 1735
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
1736
		strncpy(uaddr->sa_data, dev->name, 14);
E
Eric Dumazet 已提交
1737
	else
L
Linus Torvalds 已提交
1738
		memset(uaddr->sa_data, 0, 14);
E
Eric Dumazet 已提交
1739
	rcu_read_unlock();
L
Linus Torvalds 已提交
1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750
	*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);
1751
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
1752 1753 1754 1755 1756 1757 1758

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
1759
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
1760 1761
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
1762 1763 1764 1765 1766 1767 1768 1769
	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
1770
	rcu_read_unlock();
1771
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
1772 1773 1774 1775

	return 0;
}

1776 1777
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
1778 1779 1780
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
1781 1782
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
1783
		if (what > 0)
1784
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
1785
		else
1786
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
1787 1788
		break;
	case PACKET_MR_PROMISC:
1789
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
1790 1791
		break;
	case PACKET_MR_ALLMULTI:
1792
		return dev_set_allmulti(dev, what);
L
Linus Torvalds 已提交
1793
		break;
1794
	case PACKET_MR_UNICAST:
1795 1796
		if (i->alen != dev->addr_len)
			return -EINVAL;
1797
		if (what > 0)
1798
			return dev_uc_add(dev, i->addr);
1799
		else
1800
			return dev_uc_del(dev, i->addr);
1801
		break;
E
Eric Dumazet 已提交
1802 1803
	default:
		break;
L
Linus Torvalds 已提交
1804
	}
1805
	return 0;
L
Linus Torvalds 已提交
1806 1807 1808 1809
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
E
Eric Dumazet 已提交
1810
	for ( ; i; i = i->next) {
L
Linus Torvalds 已提交
1811 1812 1813 1814 1815
		if (i->ifindex == dev->ifindex)
			packet_dev_mc(dev, i, what);
	}
}

1816
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1817 1818 1819 1820 1821 1822 1823 1824 1825
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
1826
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
1827 1828 1829 1830
	if (!dev)
		goto done;

	err = -EINVAL;
1831
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
1832 1833 1834
		goto done;

	err = -ENOBUFS;
1835
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
	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;
1859 1860 1861 1862 1863
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
1864 1865 1866 1867 1868 1869

done:
	rtnl_unlock();
	return err;
}

1870
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883
{
	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;
1884 1885
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909
					packet_dev_mc(dev, ml, -1);
				kfree(ml);
			}
			rtnl_unlock();
			return 0;
		}
	}
	rtnl_unlock();
	return -EADDRNOTAVAIL;
}

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;
1910 1911
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
1912 1913 1914 1915 1916 1917 1918
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
1919
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
1920 1921
{
	struct sock *sk = sock->sk;
1922
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
1923 1924 1925 1926 1927
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
1928
	switch (optname) {
1929
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
1930 1931
	case PACKET_DROP_MEMBERSHIP:
	{
1932 1933 1934 1935
		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
1936
			return -EINVAL;
1937 1938
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
1939
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
1940
			return -EFAULT;
1941 1942
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
1943 1944 1945 1946 1947 1948
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
1949

L
Linus Torvalds 已提交
1950
	case PACKET_RX_RING:
J
Johann Baudy 已提交
1951
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
1952 1953 1954
	{
		struct tpacket_req req;

E
Eric Dumazet 已提交
1955
		if (optlen < sizeof(req))
L
Linus Torvalds 已提交
1956
			return -EINVAL;
1957 1958
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
E
Eric Dumazet 已提交
1959
		if (copy_from_user(&req, optval, sizeof(req)))
L
Linus Torvalds 已提交
1960
			return -EFAULT;
J
Johann Baudy 已提交
1961
		return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
1962 1963 1964 1965 1966
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
1967
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
1968
			return -EINVAL;
E
Eric Dumazet 已提交
1969
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
1970 1971 1972 1973 1974
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
1975 1976 1977 1978 1979 1980
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
1981
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
		case TPACKET_V2:
			po->tp_version = val;
			return 0;
		default:
			return -EINVAL;
		}
	}
1994 1995 1996 1997 1998 1999
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
2000
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2001 2002 2003 2004 2005 2006
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
	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;
	}
2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031
	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;
	}
2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043
	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;
	}
2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059
	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;
	}
2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071
	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;
	}
L
Linus Torvalds 已提交
2072 2073 2074 2075 2076 2077 2078 2079 2080
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
2081
	int val;
L
Linus Torvalds 已提交
2082 2083
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
2084 2085
	void *data;
	struct tpacket_stats st;
L
Linus Torvalds 已提交
2086 2087 2088 2089

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

2090 2091
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
2092 2093 2094

	if (len < 0)
		return -EINVAL;
2095

J
Johann Baudy 已提交
2096
	switch (optname) {
L
Linus Torvalds 已提交
2097 2098 2099 2100 2101 2102 2103 2104 2105
	case PACKET_STATISTICS:
		if (len > sizeof(struct tpacket_stats))
			len = sizeof(struct tpacket_stats);
		spin_lock_bh(&sk->sk_receive_queue.lock);
		st = po->stats;
		memset(&po->stats, 0, sizeof(st));
		spin_unlock_bh(&sk->sk_receive_queue.lock);
		st.tp_packets += st.tp_drops;

2106 2107 2108 2109 2110 2111 2112
		data = &st;
		break;
	case PACKET_AUXDATA:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->auxdata;

2113 2114 2115 2116 2117 2118 2119
		data = &val;
		break;
	case PACKET_ORIGDEV:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->origdev;

2120 2121 2122 2123 2124 2125 2126
		data = &val;
		break;
	case PACKET_VNET_HDR:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->has_vnet_hdr;

2127
		data = &val;
L
Linus Torvalds 已提交
2128
		break;
2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151
	case PACKET_VERSION:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->tp_version;
		data = &val;
		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;
		default:
			return -EINVAL;
		}
		data = &val;
		break;
2152 2153 2154 2155 2156 2157
	case PACKET_RESERVE:
		if (len > sizeof(unsigned int))
			len = sizeof(unsigned int);
		val = po->tp_reserve;
		data = &val;
		break;
J
Johann Baudy 已提交
2158 2159 2160 2161 2162 2163
	case PACKET_LOSS:
		if (len > sizeof(unsigned int))
			len = sizeof(unsigned int);
		val = po->tp_loss;
		data = &val;
		break;
2164 2165 2166 2167 2168 2169
	case PACKET_TIMESTAMP:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->tp_tstamp;
		data = &val;
		break;
L
Linus Torvalds 已提交
2170 2171 2172 2173
	default:
		return -ENOPROTOOPT;
	}

2174 2175
	if (put_user(len, optlen))
		return -EFAULT;
2176 2177
	if (copy_to_user(optval, data, len))
		return -EFAULT;
2178
	return 0;
L
Linus Torvalds 已提交
2179 2180 2181 2182 2183 2184 2185
}


static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
{
	struct sock *sk;
	struct hlist_node *node;
2186
	struct net_device *dev = data;
2187
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
2188

2189 2190
	rcu_read_lock();
	sk_for_each_rcu(sk, node, &net->packet.sklist) {
L
Linus Torvalds 已提交
2191 2192 2193 2194 2195 2196
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
				packet_dev_mclist(dev, po->mclist, -1);
2197 2198
			/* fallthrough */

L
Linus Torvalds 已提交
2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217
		case NETDEV_DOWN:
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->running) {
					__dev_remove_pack(&po->prot_hook);
					__sock_put(sk);
					po->running = 0;
					sk->sk_err = ENETDOWN;
					if (!sock_flag(sk, SOCK_DEAD))
						sk->sk_error_report(sk);
				}
				if (msg == NETDEV_UNREGISTER) {
					po->ifindex = -1;
					po->prot_hook.dev = NULL;
				}
				spin_unlock(&po->bind_lock);
			}
			break;
		case NETDEV_UP:
2218 2219 2220 2221 2222 2223 2224 2225
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->num && !po->running) {
					dev_add_pack(&po->prot_hook);
					sock_hold(sk);
					po->running = 1;
				}
				spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
2226 2227 2228 2229
			}
			break;
		}
	}
2230
	rcu_read_unlock();
L
Linus Torvalds 已提交
2231 2232 2233 2234 2235 2236 2237 2238 2239
	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
2240
	switch (cmd) {
E
Eric Dumazet 已提交
2241 2242 2243
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
2244

E
Eric Dumazet 已提交
2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262
		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);
2263

L
Linus Torvalds 已提交
2264
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279
	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
2280 2281
#endif

E
Eric Dumazet 已提交
2282 2283
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
2284 2285 2286 2287
	}
	return 0;
}

E
Eric Dumazet 已提交
2288
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
2289 2290 2291 2292 2293 2294 2295
				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
2296 2297
	if (po->rx_ring.pg_vec) {
		if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
2298 2299 2300
			mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
2301 2302 2303 2304 2305 2306
	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
2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317
	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
2318
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2319
	struct sock *sk = sock->sk;
2320

L
Linus Torvalds 已提交
2321 2322 2323 2324 2325 2326 2327
	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
2328
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2329
	struct sock *sk = sock->sk;
2330

L
Linus Torvalds 已提交
2331 2332 2333 2334
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

2335
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
2336 2337
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
2338 2339
};

2340 2341
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
2342 2343 2344
{
	int i;

2345
	for (i = 0; i < len; i++) {
2346
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
2347
			if (is_vmalloc_addr(pg_vec[i].buffer))
2348 2349 2350 2351 2352 2353
				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
2354 2355 2356 2357
	}
	kfree(pg_vec);
}

C
Changli Gao 已提交
2358
static inline char *alloc_one_pg_vec_page(unsigned long order)
2359
{
2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371
	char *buffer = NULL;
	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;

	/*
	 * __get_free_pages failed, fall back to vmalloc
	 */
E
Eric Dumazet 已提交
2372
	buffer = vzalloc((1 << order) * PAGE_SIZE);
2373

2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388
	if (buffer)
		return buffer;

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

	/*
	 * complete and utter failure
	 */
	return NULL;
2389 2390
}

2391
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2392 2393
{
	unsigned int block_nr = req->tp_block_nr;
2394
	struct pgv *pg_vec;
2395 2396
	int i;

2397
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2398 2399 2400 2401
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
2402
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2403
		if (unlikely(!pg_vec[i].buffer))
2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414
			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
2415

J
Johann Baudy 已提交
2416 2417
static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
		int closing, int tx_ring)
L
Linus Torvalds 已提交
2418
{
2419
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
2420
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
2421
	int was_running, order = 0;
J
Johann Baudy 已提交
2422 2423
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
2424
	__be16 num;
J
Johann Baudy 已提交
2425
	int err;
2426

J
Johann Baudy 已提交
2427 2428
	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
2429

J
Johann Baudy 已提交
2430 2431 2432 2433 2434 2435 2436
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
		if (atomic_read(&rb->pending))
			goto out;
	}
L
Linus Torvalds 已提交
2437

J
Johann Baudy 已提交
2438 2439 2440 2441 2442
	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
2443

2444 2445 2446 2447 2448 2449 2450 2451 2452
		switch (po->tp_version) {
		case TPACKET_V1:
			po->tp_hdrlen = TPACKET_HDRLEN;
			break;
		case TPACKET_V2:
			po->tp_hdrlen = TPACKET2_HDRLEN;
			break;
		}

J
Johann Baudy 已提交
2453
		err = -EINVAL;
2454
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
2455
			goto out;
2456
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
2457
			goto out;
2458
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
2459 2460
					po->tp_reserve))
			goto out;
2461
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
2462
			goto out;
L
Linus Torvalds 已提交
2463

J
Johann Baudy 已提交
2464 2465 2466 2467 2468 2469
		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
2470 2471

		err = -ENOMEM;
2472 2473 2474
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
2475
			goto out;
J
Johann Baudy 已提交
2476 2477 2478 2479
	}
	/* Done */
	else {
		err = -EINVAL;
2480
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
2481
			goto out;
L
Linus Torvalds 已提交
2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496
	}

	lock_sock(sk);

	/* Detach socket from network */
	spin_lock(&po->bind_lock);
	was_running = po->running;
	num = po->num;
	if (was_running) {
		__dev_remove_pack(&po->prot_hook);
		po->num = 0;
		po->running = 0;
		__sock_put(sk);
	}
	spin_unlock(&po->bind_lock);
2497

L
Linus Torvalds 已提交
2498 2499 2500
	synchronize_net();

	err = -EBUSY;
2501
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2502 2503
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
2504
		spin_lock_bh(&rb_queue->lock);
2505
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
2506 2507 2508 2509 2510
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

2511 2512
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
2513 2514 2515 2516 2517

		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
2518
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
2519 2520
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
2521
	}
2522
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540

	spin_lock(&po->bind_lock);
	if (was_running && !po->running) {
		sock_hold(sk);
		po->running = 1;
		po->num = num;
		dev_add_pack(&po->prot_hook);
	}
	spin_unlock(&po->bind_lock);

	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
2541 2542
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
2543 2544 2545
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
2546 2547
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
2548 2549 2550 2551 2552 2553 2554
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

2555
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566

	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
2567
		goto out;
J
Johann Baudy 已提交
2568 2569 2570

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
2571 2572 2573
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
2574 2575 2576 2577 2578
	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++) {
2579 2580
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
2581 2582
			int pg_num;

C
Changli Gao 已提交
2583 2584
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
2585 2586 2587 2588
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
2589
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
2590
			}
2591
		}
L
Linus Torvalds 已提交
2592
	}
J
Johann Baudy 已提交
2593

2594
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
2595 2596 2597 2598
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
2599
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2600 2601 2602
	return err;
}

2603
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623
	.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,
};

2624
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
2625 2626 2627 2628 2629 2630 2631
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
2632
	.getname =	packet_getname,
L
Linus Torvalds 已提交
2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644
	.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,
};

2645
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
2646 2647 2648 2649 2650 2651
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
2652
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
2653 2654 2655 2656 2657
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2658
	__acquires(RCU)
L
Linus Torvalds 已提交
2659
{
2660
	struct net *net = seq_file_net(seq);
2661 2662 2663

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
2664 2665 2666 2667
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
2668
	struct net *net = seq_file_net(seq);
2669
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
2670 2671 2672
}

static void packet_seq_stop(struct seq_file *seq, void *v)
2673
	__releases(RCU)
L
Linus Torvalds 已提交
2674
{
2675
	rcu_read_unlock();
L
Linus Torvalds 已提交
2676 2677
}

2678
static int packet_seq_show(struct seq_file *seq, void *v)
L
Linus Torvalds 已提交
2679 2680 2681 2682
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
2683
		struct sock *s = sk_entry(v);
L
Linus Torvalds 已提交
2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695
		const struct packet_sock *po = pkt_sk(s);

		seq_printf(seq,
			   "%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
			   s,
			   atomic_read(&s->sk_refcnt),
			   s->sk_type,
			   ntohs(po->num),
			   po->ifindex,
			   po->running,
			   atomic_read(&s->sk_rmem_alloc),
			   sock_i_uid(s),
E
Eric Dumazet 已提交
2696
			   sock_i_ino(s));
L
Linus Torvalds 已提交
2697 2698 2699 2700 2701
	}

	return 0;
}

2702
static const struct seq_operations packet_seq_ops = {
L
Linus Torvalds 已提交
2703 2704 2705 2706 2707 2708 2709 2710
	.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)
{
2711 2712
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
2713 2714
}

2715
static const struct file_operations packet_seq_fops = {
L
Linus Torvalds 已提交
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	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
2720
	.release	= seq_release_net,
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};

#endif

2725
static int __net_init packet_net_init(struct net *net)
2726
{
2727
	spin_lock_init(&net->packet.sklist_lock);
2728
	INIT_HLIST_HEAD(&net->packet.sklist);
2729 2730 2731 2732 2733 2734 2735

	if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
		return -ENOMEM;

	return 0;
}

2736
static void __net_exit packet_net_exit(struct net *net)
2737 2738 2739 2740 2741 2742 2743 2744 2745 2746
{
	proc_net_remove(net, "packet");
}

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


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static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
2750
	unregister_pernet_subsys(&packet_net_ops);
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	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);
2763
	register_pernet_subsys(&packet_net_ops);
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	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);