af_packet.c 61.8 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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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 + VLAN_HLEN)
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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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	if (len > (dev->mtu + dev->hard_header_len)) {
		/* 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;
		}
	}
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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();
	filter = rcu_dereference(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();
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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;
E
Eric Dumazet 已提交
565
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
566
	int skb_len = skb->len;
D
David S. Miller 已提交
567
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
568 569 570 571 572 573 574

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

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

O
Octavian Purdila 已提交
575
	if (!net_eq(dev_net(dev), sock_net(sk)))
576 577
		goto drop;

L
Linus Torvalds 已提交
578 579
	skb->dev = dev;

580
	if (dev->header_ops) {
L
Linus Torvalds 已提交
581
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
582 583 584 585 586
		 * 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
587 588
		 */
		if (sk->sk_type != SOCK_DGRAM)
589
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
590 591
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
592
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
593 594 595 596 597
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
598 599
	res = run_filter(skb, sk, snaplen);
	if (!res)
600
		goto drop_n_restore;
D
David S. Miller 已提交
601 602
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620

	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;
	}

621 622 623 624
	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
625 626 627 628
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
629
	if (unlikely(po->origdev))
630 631 632
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
633

S
Stephen Hemminger 已提交
634
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
635

636
	PACKET_SKB_CB(skb)->origlen = skb->len;
637

L
Linus Torvalds 已提交
638 639 640 641 642
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
643
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
644

645 646 647
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
648 649
	spin_lock(&sk->sk_receive_queue.lock);
	po->stats.tp_packets++;
650
	skb->dropcount = atomic_read(&sk->sk_drops);
L
Linus Torvalds 已提交
651 652 653 654 655 656
	__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:
657
	po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
L
Linus Torvalds 已提交
658 659 660 661 662 663 664

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
665
	consume_skb(skb);
L
Linus Torvalds 已提交
666 667 668
	return 0;
}

E
Eric Dumazet 已提交
669 670
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
671 672 673 674
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
675 676 677 678 679
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
		void *raw;
	} h;
E
Eric Dumazet 已提交
680
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
681
	int skb_len = skb->len;
D
David S. Miller 已提交
682
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
683
	unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
684
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
685
	struct sk_buff *copy_skb = NULL;
686
	struct timeval tv;
687
	struct timespec ts;
688
	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
L
Linus Torvalds 已提交
689 690 691 692 693 694 695

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

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

O
Octavian Purdila 已提交
696
	if (!net_eq(dev_net(dev), sock_net(sk)))
697 698
		goto drop;

699
	if (dev->header_ops) {
L
Linus Torvalds 已提交
700
		if (sk->sk_type != SOCK_DGRAM)
701
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
702 703
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
704
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
705 706 707
		}
	}

708 709 710
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;

L
Linus Torvalds 已提交
711 712
	snaplen = skb->len;

D
David S. Miller 已提交
713 714
	res = run_filter(skb, sk, snaplen);
	if (!res)
715
		goto drop_n_restore;
D
David S. Miller 已提交
716 717
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
718 719

	if (sk->sk_type == SOCK_DGRAM) {
720 721
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
722
	} else {
723
		unsigned maclen = skb_network_offset(skb);
724
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
725 726
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
727 728 729
		macoff = netoff - maclen;
	}

J
Johann Baudy 已提交
730
	if (macoff + snaplen > po->rx_ring.frame_size) {
L
Linus Torvalds 已提交
731 732 733 734 735 736 737 738 739 740 741 742
		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
743
		snaplen = po->rx_ring.frame_size - macoff;
L
Linus Torvalds 已提交
744 745 746 747 748
		if ((int)snaplen < 0)
			snaplen = 0;
	}

	spin_lock(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
749
	h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
750
	if (!h.raw)
L
Linus Torvalds 已提交
751
		goto ring_is_full;
J
Johann Baudy 已提交
752
	packet_increment_head(&po->rx_ring);
L
Linus Torvalds 已提交
753 754 755 756 757 758 759 760 761
	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);

762
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
L
Linus Torvalds 已提交
763

764 765 766 767 768 769
	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;
770 771 772 773 774 775 776
		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)
777 778 779 780 781 782 783 784 785 786 787 788
			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;
789 790 791 792 793 794 795
		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)
796 797 798 799 800
			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
801
		h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
802 803 804 805 806
		hdrlen = sizeof(*h.h2);
		break;
	default:
		BUG();
	}
L
Linus Torvalds 已提交
807

808
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
809
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
810 811 812 813
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
814
	if (unlikely(po->origdev))
815 816 817
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
818

819
	__packet_set_status(po, h.raw, status);
R
Ralf Baechle 已提交
820
	smp_mb();
821
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
L
Linus Torvalds 已提交
822
	{
823 824 825 826 827
		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
828
	}
829
#endif
L
Linus Torvalds 已提交
830 831 832 833 834 835 836 837 838

	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:
839
	kfree_skb(skb);
L
Linus Torvalds 已提交
840 841 842 843 844 845 846
	return 0;

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

	sk->sk_data_ready(sk, 0);
847
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
848 849 850
	goto drop_n_restore;
}

J
Johann Baudy 已提交
851 852 853
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
E
Eric Dumazet 已提交
854
	void *ph;
L
Linus Torvalds 已提交
855

J
Johann Baudy 已提交
856
	BUG_ON(skb == NULL);
L
Linus Torvalds 已提交
857

J
Johann Baudy 已提交
858 859 860 861 862 863 864 865 866 867 868
	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
869 870 871
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
872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888
{
	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;
889
	skb->mark = po->sk.sk_mark;
J
Johann Baudy 已提交
890 891 892 893 894 895 896 897 898 899 900
	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
901
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
J
Johann Baudy 已提交
902 903 904 905 906 907 908 909 910 911 912 913 914 915
		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
916
	} else if (dev->hard_header_len) {
J
Johann Baudy 已提交
917 918
		/* net device doesn't like empty head */
		if (unlikely(tp_len <= dev->hard_header_len)) {
E
Eric Dumazet 已提交
919 920
			pr_err("packet size is too short (%d < %d)\n",
			       tp_len, dev->hard_header_len);
J
Johann Baudy 已提交
921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947
			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
948 949
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
950 951 952
			return -EFAULT;
		}

953 954
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
955 956
		flush_dcache_page(page);
		get_page(page);
957
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
958 959 960 961 962 963 964 965 966 967 968 969 970 971 972
		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;
	int ifindex, err, reserve = 0;
E
Eric Dumazet 已提交
973 974
	void *ph;
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
J
Johann Baudy 已提交
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 1003 1004 1005 1006 1007 1008 1009 1010 1011
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
	int status = 0;

	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
1012
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
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 1049 1050 1051 1052 1053 1054 1055 1056 1057

	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);
1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071
		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
1072 1073
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
1074 1075 1076 1077
	} while (likely((ph != NULL) ||
			((!(msg->msg_flags & MSG_DONTWAIT)) &&
			 (atomic_read(&po->tx_ring.pending))))
		);
J
Johann Baudy 已提交
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091

	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;
}

1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115
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
1116
static int packet_snd(struct socket *sock,
L
Linus Torvalds 已提交
1117 1118 1119
			  struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
1120
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
L
Linus Torvalds 已提交
1121 1122
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
1123
	__be16 proto;
L
Linus Torvalds 已提交
1124 1125
	unsigned char *addr;
	int ifindex, err, reserve = 0;
1126 1127 1128 1129 1130
	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
1131 1132

	/*
1133
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1134
	 */
1135

L
Linus Torvalds 已提交
1136 1137 1138 1139 1140 1141 1142 1143
	if (saddr == NULL) {
		ifindex	= po->ifindex;
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
1144 1145
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
1146 1147 1148 1149 1150 1151
		ifindex	= saddr->sll_ifindex;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
	}


1152
	dev = dev_get_by_index(sock_net(sk), ifindex);
L
Linus Torvalds 已提交
1153 1154 1155 1156 1157 1158
	err = -ENXIO;
	if (dev == NULL)
		goto out_unlock;
	if (sock->type == SOCK_RAW)
		reserve = dev->hard_header_len;

1159 1160 1161 1162
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

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 1202 1203 1204 1205 1206 1207 1208 1209 1210
	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
1211
	err = -EMSGSIZE;
1212
	if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
L
Linus Torvalds 已提交
1213 1214
		goto out_unlock;

1215 1216 1217 1218
	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
1219
	if (skb == NULL)
L
Linus Torvalds 已提交
1220 1221
		goto out_unlock;

1222
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
1223

1224 1225
	err = -EINVAL;
	if (sock->type == SOCK_DGRAM &&
1226
	    (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1227
		goto out_free;
L
Linus Torvalds 已提交
1228 1229

	/* Returns -EFAULT on error */
1230
	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
L
Linus Torvalds 已提交
1231 1232
	if (err)
		goto out_free;
1233
	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1234 1235
	if (err < 0)
		goto out_free;
L
Linus Torvalds 已提交
1236

1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250
	if (!gso_type && (len > dev->mtu + reserve)) {
		/* 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;
		}
	}

L
Linus Torvalds 已提交
1251 1252 1253
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1254
	skb->mark = sk->sk_mark;
L
Linus Torvalds 已提交
1255

1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
	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
1275 1276 1277 1278 1279 1280 1281 1282 1283 1284
	/*
	 *	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
1285
	return len;
L
Linus Torvalds 已提交
1286 1287 1288 1289 1290 1291 1292 1293 1294 1295

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

J
Johann Baudy 已提交
1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306
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
1307 1308 1309 1310 1311 1312 1313 1314 1315
/*
 *	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;
1316
	struct net *net;
J
Johann Baudy 已提交
1317
	struct tpacket_req req;
L
Linus Torvalds 已提交
1318 1319 1320 1321

	if (!sk)
		return 0;

1322
	net = sock_net(sk);
L
Linus Torvalds 已提交
1323 1324
	po = pkt_sk(sk);

1325 1326
	spin_lock_bh(&net->packet.sklist_lock);
	sk_del_node_init_rcu(sk);
1327
	sock_prot_inuse_add(net, sk->sk_prot, -1);
1328
	spin_unlock_bh(&net->packet.sklist_lock);
L
Linus Torvalds 已提交
1329

1330
	spin_lock(&po->bind_lock);
L
Linus Torvalds 已提交
1331 1332
	if (po->running) {
		/*
1333
		 * Remove from protocol table
L
Linus Torvalds 已提交
1334 1335 1336
		 */
		po->running = 0;
		po->num = 0;
1337
		__dev_remove_pack(&po->prot_hook);
L
Linus Torvalds 已提交
1338 1339
		__sock_put(sk);
	}
1340
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
1341 1342 1343

	packet_flush_mclist(sk);

J
Johann Baudy 已提交
1344 1345 1346 1347 1348 1349 1350
	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
1351

1352
	synchronize_net();
L
Linus Torvalds 已提交
1353 1354 1355 1356 1357 1358 1359 1360 1361
	/*
	 *	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);
1362
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
1363 1364 1365 1366 1367 1368 1369 1370 1371

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

A
Al Viro 已提交
1372
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
L
Linus Torvalds 已提交
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399
{
	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;

1400
	if (!dev || (dev->flags & IFF_UP)) {
L
Linus Torvalds 已提交
1401 1402 1403
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
1404 1405 1406 1407
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419
	}

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
1420 1421
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
1422
{
E
Eric Dumazet 已提交
1423
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1424 1425 1426
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
1427

L
Linus Torvalds 已提交
1428 1429 1430
	/*
	 *	Check legality
	 */
1431

1432
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
1433
		return -EINVAL;
E
Eric Dumazet 已提交
1434
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
1435

1436
	dev = dev_get_by_name(sock_net(sk), name);
L
Linus Torvalds 已提交
1437 1438 1439 1440 1441 1442 1443 1444 1445
	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
1446 1447
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
1448 1449 1450 1451 1452 1453 1454
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
1455

L
Linus Torvalds 已提交
1456 1457 1458 1459 1460 1461 1462
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
1463
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481
		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),
};

/*
1482
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
1483 1484
 */

1485 1486
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
1487 1488 1489
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
1490
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
1491 1492 1493 1494
	int err;

	if (!capable(CAP_NET_RAW))
		return -EPERM;
1495 1496
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
1497 1498 1499 1500 1501
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
1502
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
L
Linus Torvalds 已提交
1503 1504 1505 1506 1507 1508
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
1509

L
Linus Torvalds 已提交
1510 1511 1512 1513
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
1514
	po->num = proto;
L
Linus Torvalds 已提交
1515 1516

	sk->sk_destruct = packet_sock_destruct;
1517
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
1518 1519 1520 1521 1522 1523

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
1524
	mutex_init(&po->pg_vec_lock);
L
Linus Torvalds 已提交
1525
	po->prot_hook.func = packet_rcv;
1526

L
Linus Torvalds 已提交
1527 1528
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
1529

L
Linus Torvalds 已提交
1530 1531
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
1532 1533
	if (proto) {
		po->prot_hook.type = proto;
L
Linus Torvalds 已提交
1534 1535 1536 1537 1538
		dev_add_pack(&po->prot_hook);
		sock_hold(sk);
		po->running = 1;
	}

1539 1540
	spin_lock_bh(&net->packet.sklist_lock);
	sk_add_node_rcu(sk, &net->packet.sklist);
1541
	sock_prot_inuse_add(net, &packet_proto, 1);
1542 1543
	spin_unlock_bh(&net->packet.sklist_lock);

E
Eric Dumazet 已提交
1544
	return 0;
L
Linus Torvalds 已提交
1545 1546 1547 1548
out:
	return err;
}

1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593
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
1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604
/*
 *	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;
1605
	struct sockaddr_ll *sll;
1606
	int vnet_hdr_len = 0;
L
Linus Torvalds 已提交
1607 1608

	err = -EINVAL;
1609
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
1610 1611 1612 1613 1614 1615 1616 1617
		goto out;

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

1618 1619 1620 1621 1622
	if (flags & MSG_ERRQUEUE) {
		err = packet_recv_error(sk, msg, len);
		goto out;
	}

L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628 1629 1630 1631
	/*
	 *	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
1632
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
1633 1634

	/*
1635
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
1636 1637 1638 1639
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

1640
	if (skb == NULL)
L
Linus Torvalds 已提交
1641 1642
		goto out;

1643 1644 1645 1646 1647
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
1648
		if (len < vnet_hdr_len)
1649 1650
			goto out_free;

1651 1652
		len -= vnet_hdr_len;

1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675
		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;
1676
			vnet_hdr.csum_start = skb_checksum_start_offset(skb);
1677 1678 1679 1680 1681 1682 1683 1684 1685
			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;
	}

1686 1687 1688 1689 1690
	/*
	 *	If the address length field is there to be filled in, we fill
	 *	it in now.
	 */

1691
	sll = &PACKET_SKB_CB(skb)->sa.ll;
1692 1693 1694 1695 1696
	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
1697 1698 1699 1700 1701 1702
	/*
	 *	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
1703 1704 1705
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
1706 1707 1708 1709 1710 1711
	}

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

1712
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
1713 1714

	if (msg->msg_name)
1715 1716
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
L
Linus Torvalds 已提交
1717

1718
	if (pkt_sk(sk)->auxdata) {
1719 1720 1721 1722 1723 1724 1725 1726
		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;
1727
		aux.tp_net = skb_network_offset(skb);
E
Eric Dumazet 已提交
1728
		aux.tp_vlan_tci = vlan_tx_tag_get(skb);
1729 1730

		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1731 1732
	}

L
Linus Torvalds 已提交
1733 1734 1735 1736
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
1737
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754

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
1755 1756 1757
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
1758
		strncpy(uaddr->sa_data, dev->name, 14);
E
Eric Dumazet 已提交
1759
	else
L
Linus Torvalds 已提交
1760
		memset(uaddr->sa_data, 0, 14);
E
Eric Dumazet 已提交
1761
	rcu_read_unlock();
L
Linus Torvalds 已提交
1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772
	*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);
1773
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
1774 1775 1776 1777 1778 1779 1780

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
1781
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
1782 1783
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
1784 1785 1786 1787 1788 1789 1790 1791
	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
1792
	rcu_read_unlock();
1793
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
1794 1795 1796 1797

	return 0;
}

1798 1799
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
1800 1801 1802
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
1803 1804
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
1805
		if (what > 0)
1806
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
1807
		else
1808
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
1809 1810
		break;
	case PACKET_MR_PROMISC:
1811
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
1812 1813
		break;
	case PACKET_MR_ALLMULTI:
1814
		return dev_set_allmulti(dev, what);
L
Linus Torvalds 已提交
1815
		break;
1816
	case PACKET_MR_UNICAST:
1817 1818
		if (i->alen != dev->addr_len)
			return -EINVAL;
1819
		if (what > 0)
1820
			return dev_uc_add(dev, i->addr);
1821
		else
1822
			return dev_uc_del(dev, i->addr);
1823
		break;
E
Eric Dumazet 已提交
1824 1825
	default:
		break;
L
Linus Torvalds 已提交
1826
	}
1827
	return 0;
L
Linus Torvalds 已提交
1828 1829 1830 1831
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
E
Eric Dumazet 已提交
1832
	for ( ; i; i = i->next) {
L
Linus Torvalds 已提交
1833 1834 1835 1836 1837
		if (i->ifindex == dev->ifindex)
			packet_dev_mc(dev, i, what);
	}
}

1838
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1839 1840 1841 1842 1843 1844 1845 1846 1847
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
1848
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
1849 1850 1851 1852
	if (!dev)
		goto done;

	err = -EINVAL;
1853
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
1854 1855 1856
		goto done;

	err = -ENOBUFS;
1857
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880
	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;
1881 1882 1883 1884 1885
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890 1891

done:
	rtnl_unlock();
	return err;
}

1892
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905
{
	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;
1906 1907
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931
					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;
1932 1933
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
1934 1935 1936 1937 1938 1939 1940
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
1941
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
1942 1943
{
	struct sock *sk = sock->sk;
1944
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
1945 1946 1947 1948 1949
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
1950
	switch (optname) {
1951
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
1952 1953
	case PACKET_DROP_MEMBERSHIP:
	{
1954 1955 1956 1957
		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
1958
			return -EINVAL;
1959 1960
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
1961
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
1962
			return -EFAULT;
1963 1964
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
1965 1966 1967 1968 1969 1970
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
1971

L
Linus Torvalds 已提交
1972
	case PACKET_RX_RING:
J
Johann Baudy 已提交
1973
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
1974 1975 1976
	{
		struct tpacket_req req;

E
Eric Dumazet 已提交
1977
		if (optlen < sizeof(req))
L
Linus Torvalds 已提交
1978
			return -EINVAL;
1979 1980
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
E
Eric Dumazet 已提交
1981
		if (copy_from_user(&req, optval, sizeof(req)))
L
Linus Torvalds 已提交
1982
			return -EFAULT;
J
Johann Baudy 已提交
1983
		return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
1984 1985 1986 1987 1988
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
1989
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
1990
			return -EINVAL;
E
Eric Dumazet 已提交
1991
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
1992 1993 1994 1995 1996
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
1997 1998 1999 2000 2001 2002
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
2003
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
			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;
		}
	}
2016 2017 2018 2019 2020 2021
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
2022
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2023 2024 2025 2026 2027 2028
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041
	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;
	}
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053
	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;
	}
2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
	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;
	}
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081
	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;
	}
2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093
	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
2094 2095 2096 2097 2098 2099 2100 2101 2102
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
2103
	int val;
L
Linus Torvalds 已提交
2104 2105
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
2106 2107
	void *data;
	struct tpacket_stats st;
L
Linus Torvalds 已提交
2108 2109 2110 2111

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

2112 2113
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
2114 2115 2116

	if (len < 0)
		return -EINVAL;
2117

J
Johann Baudy 已提交
2118
	switch (optname) {
L
Linus Torvalds 已提交
2119 2120 2121 2122 2123 2124 2125 2126 2127
	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;

2128 2129 2130 2131 2132 2133 2134
		data = &st;
		break;
	case PACKET_AUXDATA:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->auxdata;

2135 2136 2137 2138 2139 2140 2141
		data = &val;
		break;
	case PACKET_ORIGDEV:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->origdev;

2142 2143 2144 2145 2146 2147 2148
		data = &val;
		break;
	case PACKET_VNET_HDR:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->has_vnet_hdr;

2149
		data = &val;
L
Linus Torvalds 已提交
2150
		break;
2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173
	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;
2174 2175 2176 2177 2178 2179
	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
2180 2181 2182 2183 2184 2185
	case PACKET_LOSS:
		if (len > sizeof(unsigned int))
			len = sizeof(unsigned int);
		val = po->tp_loss;
		data = &val;
		break;
2186 2187 2188 2189 2190 2191
	case PACKET_TIMESTAMP:
		if (len > sizeof(int))
			len = sizeof(int);
		val = po->tp_tstamp;
		data = &val;
		break;
L
Linus Torvalds 已提交
2192 2193 2194 2195
	default:
		return -ENOPROTOOPT;
	}

2196 2197
	if (put_user(len, optlen))
		return -EFAULT;
2198 2199
	if (copy_to_user(optval, data, len))
		return -EFAULT;
2200
	return 0;
L
Linus Torvalds 已提交
2201 2202 2203 2204 2205 2206 2207
}


static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
{
	struct sock *sk;
	struct hlist_node *node;
2208
	struct net_device *dev = data;
2209
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
2210

2211 2212
	rcu_read_lock();
	sk_for_each_rcu(sk, node, &net->packet.sklist) {
L
Linus Torvalds 已提交
2213 2214 2215 2216 2217 2218
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
				packet_dev_mclist(dev, po->mclist, -1);
2219 2220
			/* fallthrough */

L
Linus Torvalds 已提交
2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239
		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:
2240 2241 2242 2243 2244 2245 2246 2247
			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
2248 2249 2250 2251
			}
			break;
		}
	}
2252
	rcu_read_unlock();
L
Linus Torvalds 已提交
2253 2254 2255 2256 2257 2258 2259 2260 2261
	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
2262
	switch (cmd) {
E
Eric Dumazet 已提交
2263 2264 2265
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
2266

E
Eric Dumazet 已提交
2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284
		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);
2285

L
Linus Torvalds 已提交
2286
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301
	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
2302 2303
#endif

E
Eric Dumazet 已提交
2304 2305
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
2306 2307 2308 2309
	}
	return 0;
}

E
Eric Dumazet 已提交
2310
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
2311 2312 2313 2314 2315 2316 2317
				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
2318 2319
	if (po->rx_ring.pg_vec) {
		if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
2320 2321 2322
			mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
2323 2324 2325 2326 2327 2328
	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
2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339
	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
2340
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2341
	struct sock *sk = sock->sk;
2342

L
Linus Torvalds 已提交
2343 2344 2345 2346 2347 2348 2349
	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
2350
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
2351
	struct sock *sk = sock->sk;
2352

L
Linus Torvalds 已提交
2353 2354 2355 2356
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

2357
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
2358 2359
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
2360 2361
};

2362 2363
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
2364 2365 2366
{
	int i;

2367
	for (i = 0; i < len; i++) {
2368
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
2369
			if (is_vmalloc_addr(pg_vec[i].buffer))
2370 2371 2372 2373 2374 2375
				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
2376 2377 2378 2379
	}
	kfree(pg_vec);
}

C
Changli Gao 已提交
2380
static inline char *alloc_one_pg_vec_page(unsigned long order)
2381
{
2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393
	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
2394
	buffer = vzalloc((1 << order) * PAGE_SIZE);
2395

2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410
	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;
2411 2412
}

2413
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2414 2415
{
	unsigned int block_nr = req->tp_block_nr;
2416
	struct pgv *pg_vec;
2417 2418
	int i;

2419
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2420 2421 2422 2423
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
2424
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2425
		if (unlikely(!pg_vec[i].buffer))
2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436
			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
2437

J
Johann Baudy 已提交
2438 2439
static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
		int closing, int tx_ring)
L
Linus Torvalds 已提交
2440
{
2441
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
2442
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
2443
	int was_running, order = 0;
J
Johann Baudy 已提交
2444 2445
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
2446
	__be16 num;
J
Johann Baudy 已提交
2447
	int err;
2448

J
Johann Baudy 已提交
2449 2450
	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
2451

J
Johann Baudy 已提交
2452 2453 2454 2455 2456 2457 2458
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
		if (atomic_read(&rb->pending))
			goto out;
	}
L
Linus Torvalds 已提交
2459

J
Johann Baudy 已提交
2460 2461 2462 2463 2464
	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
2465

2466 2467 2468 2469 2470 2471 2472 2473 2474
		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
2475
		err = -EINVAL;
2476
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
2477
			goto out;
2478
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
2479
			goto out;
2480
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
2481 2482
					po->tp_reserve))
			goto out;
2483
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
2484
			goto out;
L
Linus Torvalds 已提交
2485

J
Johann Baudy 已提交
2486 2487 2488 2489 2490 2491
		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
2492 2493

		err = -ENOMEM;
2494 2495 2496
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
2497
			goto out;
J
Johann Baudy 已提交
2498 2499 2500 2501
	}
	/* Done */
	else {
		err = -EINVAL;
2502
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
2503
			goto out;
L
Linus Torvalds 已提交
2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518
	}

	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);
2519

L
Linus Torvalds 已提交
2520 2521 2522
	synchronize_net();

	err = -EBUSY;
2523
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2524 2525
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
2526
		spin_lock_bh(&rb_queue->lock);
2527
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
2528 2529 2530 2531 2532
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

2533 2534
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
2535 2536 2537 2538 2539

		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
2540
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
2541 2542
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
2543
	}
2544
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562

	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
2563 2564
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
2565 2566 2567
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
2568 2569
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
2570 2571 2572 2573 2574 2575 2576
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

2577
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588

	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
2589
		goto out;
J
Johann Baudy 已提交
2590 2591 2592

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
2593 2594 2595
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
2596 2597 2598 2599 2600
	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++) {
2601 2602
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
2603 2604
			int pg_num;

C
Changli Gao 已提交
2605 2606
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
2607 2608 2609 2610
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
2611
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
2612
			}
2613
		}
L
Linus Torvalds 已提交
2614
	}
J
Johann Baudy 已提交
2615

2616
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
2617 2618 2619 2620
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
2621
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2622 2623 2624
	return err;
}

2625
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645
	.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,
};

2646
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
2647 2648 2649 2650 2651 2652 2653
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
2654
	.getname =	packet_getname,
L
Linus Torvalds 已提交
2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666
	.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,
};

2667
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
2668 2669 2670 2671 2672 2673
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
2674
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
2675 2676 2677 2678 2679
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2680
	__acquires(RCU)
L
Linus Torvalds 已提交
2681
{
2682
	struct net *net = seq_file_net(seq);
2683 2684 2685

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
2686 2687 2688 2689
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
2690
	struct net *net = seq_file_net(seq);
2691
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
2692 2693 2694
}

static void packet_seq_stop(struct seq_file *seq, void *v)
2695
	__releases(RCU)
L
Linus Torvalds 已提交
2696
{
2697
	rcu_read_unlock();
L
Linus Torvalds 已提交
2698 2699
}

2700
static int packet_seq_show(struct seq_file *seq, void *v)
L
Linus Torvalds 已提交
2701 2702 2703 2704
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
2705
		struct sock *s = sk_entry(v);
L
Linus Torvalds 已提交
2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717
		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
2718
			   sock_i_ino(s));
L
Linus Torvalds 已提交
2719 2720 2721 2722 2723
	}

	return 0;
}

2724
static const struct seq_operations packet_seq_ops = {
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	.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)
{
2733 2734
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
2735 2736
}

2737
static const struct file_operations packet_seq_fops = {
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2738 2739 2740 2741
	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
2742
	.release	= seq_release_net,
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Linus Torvalds 已提交
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};

#endif

2747
static int __net_init packet_net_init(struct net *net)
2748
{
2749
	spin_lock_init(&net->packet.sklist_lock);
2750
	INIT_HLIST_HEAD(&net->packet.sklist);
2751 2752 2753 2754 2755 2756 2757

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

	return 0;
}

2758
static void __net_exit packet_net_exit(struct net *net)
2759 2760 2761 2762 2763 2764 2765 2766 2767 2768
{
	proc_net_remove(net, "packet");
}

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


L
Linus Torvalds 已提交
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static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
2772
	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);
2785
	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);