af_packet.c 88.6 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		PACKET - implements raw packet sockets.
 *
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 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
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 * Fixes:
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 *		Alan Cox	:	verify_area() now used correctly
 *		Alan Cox	:	new skbuff lists, look ma no backlogs!
 *		Alan Cox	:	tidied skbuff lists.
 *		Alan Cox	:	Now uses generic datagram routines I
 *					added. Also fixed the peek/read crash
 *					from all old Linux datagram code.
 *		Alan Cox	:	Uses the improved datagram code.
 *		Alan Cox	:	Added NULL's for socket options.
 *		Alan Cox	:	Re-commented the code.
 *		Alan Cox	:	Use new kernel side addressing
 *		Rob Janssen	:	Correct MTU usage.
 *		Dave Platt	:	Counter leaks caused by incorrect
 *					interrupt locking and some slightly
 *					dubious gcc output. Can you read
 *					compiler: it said _VOLATILE_
 *	Richard Kooijman	:	Timestamp fixes.
 *		Alan Cox	:	New buffers. Use sk->mac.raw.
 *		Alan Cox	:	sendmsg/recvmsg support.
 *		Alan Cox	:	Protocol setting support
 *	Alexey Kuznetsov	:	Untied from IPv4 stack.
 *	Cyrus Durgin		:	Fixed kerneld for kmod.
 *	Michal Ostrowski        :       Module initialization cleanup.
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 *         Ulises Alonso        :       Frame number limit removal and
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 *                                      packet_set_ring memory leak.
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 *		Eric Biederman	:	Allow for > 8 byte hardware addresses.
 *					The convention is that longer addresses
 *					will simply extend the hardware address
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 *					byte arrays at the end of sockaddr_ll
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 *					and packet_mreq.
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 *		Johann Baudy	:	Added TX RING.
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 *		Chetan Loke	:	Implemented TPACKET_V3 block abstraction
 *					layer.
 *					Copyright (C) 2011, <lokec@ccs.neu.edu>
 *
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 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */
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#include <linux/types.h>
#include <linux/mm.h>
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#include <linux/capability.h>
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#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
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#include <linux/kernel.h>
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#include <linux/kmod.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <net/net_namespace.h>
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#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/page.h>
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#include <asm/cacheflush.h>
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#include <asm/io.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/if_vlan.h>
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#include <linux/virtio_net.h>
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#include <linux/errqueue.h>
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#include <linux/net_tstamp.h>
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#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif

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#include "internal.h"

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

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

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


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

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

/* Private packet socket structures. */

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/* identical to struct packet_mreq except it has
 * a longer address field.
 */
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struct packet_mreq_max {
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	int		mr_ifindex;
	unsigned short	mr_type;
	unsigned short	mr_alen;
	unsigned char	mr_address[MAX_ADDR_LEN];
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};
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static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
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		int closing, int tx_ring);

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#define V3_ALIGNMENT	(8)

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

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

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

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

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

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

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

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

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

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

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

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static inline __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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	case TPACKET_V3:
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	default:
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		WARN(1, "TPACKET version not supported.\n");
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		BUG();
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	}
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	smp_wmb();
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}

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static int __packet_get_status(struct packet_sock *po, void *frame)
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{
	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;
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	case TPACKET_V3:
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	default:
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		WARN(1, "TPACKET version not supported.\n");
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		BUG();
		return 0;
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	}
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}
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static 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;
}

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

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

static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
		int tx_ring,
		struct sk_buff_head *rb_queue)
{
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	struct tpacket_kbdq_core *pkc;
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	pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;

	spin_lock(&rb_queue->lock);
	pkc->delete_blk_timer = 1;
	spin_unlock(&rb_queue->lock);

	prb_del_retire_blk_timer(pkc);
}

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

static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
{
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	struct tpacket_kbdq_core *pkc;
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	if (tx_ring)
		BUG();

	pkc = tx_ring ? &po->tx_ring.prb_bdqc : &po->rx_ring.prb_bdqc;
	prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
}

static int prb_calc_retire_blk_tmo(struct packet_sock *po,
				int blk_size_in_bytes)
{
	struct net_device *dev;
	unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
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	struct ethtool_cmd ecmd;
	int err;
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	u32 speed;
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	rtnl_lock();
	dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
	if (unlikely(!dev)) {
		rtnl_unlock();
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		return DEFAULT_PRB_RETIRE_TOV;
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	}
	err = __ethtool_get_settings(dev, &ecmd);
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	speed = ethtool_cmd_speed(&ecmd);
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	rtnl_unlock();
	if (!err) {
		/*
		 * If the link speed is so slow you don't really
		 * need to worry about perf anyways
		 */
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		if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
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			return DEFAULT_PRB_RETIRE_TOV;
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		} else {
			msec = 1;
			div = speed / 1000;
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		}
	}

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

	if (div)
		mbits /= div;

	tmo = mbits * msec;

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

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static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
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			union tpacket_req_u *req_u)
{
	p1->feature_req_word = req_u->req3.tp_feature_req_word;
}

static void init_prb_bdqc(struct packet_sock *po,
			struct packet_ring_buffer *rb,
			struct pgv *pg_vec,
			union tpacket_req_u *req_u, int tx_ring)
{
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	struct tpacket_kbdq_core *p1 = &rb->prb_bdqc;
	struct tpacket_block_desc *pbd;
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	memset(p1, 0x0, sizeof(*p1));

	p1->knxt_seq_num = 1;
	p1->pkbdq = pg_vec;
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	pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
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	p1->pkblk_start	= pg_vec[0].buffer;
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	p1->kblk_size = req_u->req3.tp_block_size;
	p1->knum_blocks	= req_u->req3.tp_block_nr;
	p1->hdrlen = po->tp_hdrlen;
	p1->version = po->tp_version;
	p1->last_kactive_blk_num = 0;
	po->stats_u.stats3.tp_freeze_q_cnt = 0;
	if (req_u->req3.tp_retire_blk_tov)
		p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
	else
		p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
						req_u->req3.tp_block_size);
	p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
	p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;

	prb_init_ft_ops(p1, req_u);
	prb_setup_retire_blk_timer(po, tx_ring);
	prb_open_block(p1, pbd);
}

/*  Do NOT update the last_blk_num first.
 *  Assumes sk_buff_head lock is held.
 */
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static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
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{
	mod_timer(&pkc->retire_blk_timer,
			jiffies + pkc->tov_in_jiffies);
	pkc->last_kactive_blk_num = pkc->kactive_blk_num;
}

/*
 * Timer logic:
 * 1) We refresh the timer only when we open a block.
 *    By doing this we don't waste cycles refreshing the timer
 *	  on packet-by-packet basis.
 *
 * With a 1MB block-size, on a 1Gbps line, it will take
 * i) ~8 ms to fill a block + ii) memcpy etc.
 * In this cut we are not accounting for the memcpy time.
 *
 * So, if the user sets the 'tmo' to 10ms then the timer
 * will never fire while the block is still getting filled
 * (which is what we want). However, the user could choose
 * to close a block early and that's fine.
 *
 * But when the timer does fire, we check whether or not to refresh it.
 * Since the tmo granularity is in msecs, it is not too expensive
 * to refresh the timer, lets say every '8' msecs.
 * Either the user can set the 'tmo' or we can derive it based on
 * a) line-speed and b) block-size.
 * prb_calc_retire_blk_tmo() calculates the tmo.
 *
 */
static void prb_retire_rx_blk_timer_expired(unsigned long data)
{
	struct packet_sock *po = (struct packet_sock *)data;
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	struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
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	unsigned int frozen;
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	struct tpacket_block_desc *pbd;
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	spin_lock(&po->sk.sk_receive_queue.lock);

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

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

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

	if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
		if (!frozen) {
			prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
			if (!prb_dispatch_next_block(pkc, po))
				goto refresh_timer;
			else
				goto out;
		} else {
			/* Case 1. Queue was frozen because user-space was
			 *	   lagging behind.
			 */
			if (prb_curr_blk_in_use(pkc, pbd)) {
				/*
				 * Ok, user-space is still behind.
				 * So just refresh the timer.
				 */
				goto refresh_timer;
			} else {
			       /* Case 2. queue was frozen,user-space caught up,
				* now the link went idle && the timer fired.
				* We don't have a block to close.So we open this
				* block and restart the timer.
				* opening a block thaws the queue,restarts timer
				* Thawing/timer-refresh is a side effect.
				*/
				prb_open_block(pkc, pbd);
				goto out;
			}
		}
	}

refresh_timer:
	_prb_refresh_rx_retire_blk_timer(pkc);

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

598
static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
599
		struct tpacket_block_desc *pbd1, __u32 status)
600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640
{
	/* Flush everything minus the block header */

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

	start = (u8 *)pbd1;

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

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

	smp_wmb();
#endif

	/* Now update the block status. */

	BLOCK_STATUS(pbd1) = status;

	/* Flush the block header */

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

	smp_wmb();
#endif
}

/*
 * Side effect:
 *
 * 1) flush the block
 * 2) Increment active_blk_num
 *
 * Note:We DONT refresh the timer on purpose.
 *	Because almost always the next block will be opened.
 */
641 642
static void prb_close_block(struct tpacket_kbdq_core *pkc1,
		struct tpacket_block_desc *pbd1,
643 644 645 646 647
		struct packet_sock *po, unsigned int stat)
{
	__u32 status = TP_STATUS_USER | stat;

	struct tpacket3_hdr *last_pkt;
648
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675

	if (po->stats.tp_drops)
		status |= TP_STATUS_LOSING;

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

	/* Get the ts of the last pkt */
	if (BLOCK_NUM_PKTS(pbd1)) {
		h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
		h1->ts_last_pkt.ts_nsec	= last_pkt->tp_nsec;
	} else {
		/* Ok, we tmo'd - so get the current time */
		struct timespec ts;
		getnstimeofday(&ts);
		h1->ts_last_pkt.ts_sec = ts.tv_sec;
		h1->ts_last_pkt.ts_nsec	= ts.tv_nsec;
	}

	smp_wmb();

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

	pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
}

676
static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
677 678 679 680 681 682 683 684 685 686 687
{
	pkc->reset_pending_on_curr_blk = 0;
}

/*
 * Side effect of opening a block:
 *
 * 1) prb_queue is thawed.
 * 2) retire_blk_timer is refreshed.
 *
 */
688 689
static void prb_open_block(struct tpacket_kbdq_core *pkc1,
	struct tpacket_block_desc *pbd1)
690 691
{
	struct timespec ts;
692
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
693 694 695 696 697 698 699 700 701 702 703 704 705 706 707

	smp_rmb();

	if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd1))) {

		/* We could have just memset this but we will lose the
		 * flexibility of making the priv area sticky
		 */
		BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
		BLOCK_NUM_PKTS(pbd1) = 0;
		BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
		getnstimeofday(&ts);
		h1->ts_first_pkt.ts_sec = ts.tv_sec;
		h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
		pkc1->pkblk_start = (char *)pbd1;
J
Joe Perches 已提交
708
		pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750
		BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
		BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
		pbd1->version = pkc1->version;
		pkc1->prev = pkc1->nxt_offset;
		pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
		prb_thaw_queue(pkc1);
		_prb_refresh_rx_retire_blk_timer(pkc1);

		smp_wmb();

		return;
	}

	WARN(1, "ERROR block:%p is NOT FREE status:%d kactive_blk_num:%d\n",
		pbd1, BLOCK_STATUS(pbd1), pkc1->kactive_blk_num);
	dump_stack();
	BUG();
}

/*
 * Queue freeze logic:
 * 1) Assume tp_block_nr = 8 blocks.
 * 2) At time 't0', user opens Rx ring.
 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
 * 4) user-space is either sleeping or processing block '0'.
 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
 *    it will close block-7,loop around and try to fill block '0'.
 *    call-flow:
 *    __packet_lookup_frame_in_block
 *      prb_retire_current_block()
 *      prb_dispatch_next_block()
 *        |->(BLOCK_STATUS == USER) evaluates to true
 *    5.1) Since block-0 is currently in-use, we just freeze the queue.
 * 6) Now there are two cases:
 *    6.1) Link goes idle right after the queue is frozen.
 *         But remember, the last open_block() refreshed the timer.
 *         When this timer expires,it will refresh itself so that we can
 *         re-open block-0 in near future.
 *    6.2) Link is busy and keeps on receiving packets. This is a simple
 *         case and __packet_lookup_frame_in_block will check if block-0
 *         is free and can now be re-used.
 */
751
static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
752 753 754 755 756 757 758 759 760 761 762 763 764 765
				  struct packet_sock *po)
{
	pkc->reset_pending_on_curr_blk = 1;
	po->stats_u.stats3.tp_freeze_q_cnt++;
}

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

/*
 * If the next block is free then we will dispatch it
 * and return a good offset.
 * Else, we will freeze the queue.
 * So, caller must check the return value.
 */
766
static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
767 768
		struct packet_sock *po)
{
769
	struct tpacket_block_desc *pbd;
770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790

	smp_rmb();

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

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

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

791
static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
792 793
		struct packet_sock *po, unsigned int status)
{
794
	struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821

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

	WARN(1, "ERROR-pbd[%d]:%p\n", pkc->kactive_blk_num, pbd);
	dump_stack();
	BUG();
}

822
static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
823
				      struct tpacket_block_desc *pbd)
824 825 826 827
{
	return TP_STATUS_USER & BLOCK_STATUS(pbd);
}

828
static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
829 830 831 832
{
	return pkc->reset_pending_on_curr_blk;
}

833
static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
834
{
835
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
836 837 838
	atomic_dec(&pkc->blk_fill_in_prog);
}

839
static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
840 841 842 843 844
			struct tpacket3_hdr *ppd)
{
	ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
}

845
static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
846 847 848 849 850
			struct tpacket3_hdr *ppd)
{
	ppd->hv1.tp_rxhash = 0;
}

851
static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
852 853 854 855 856 857 858 859 860 861
			struct tpacket3_hdr *ppd)
{
	if (vlan_tx_tag_present(pkc->skb)) {
		ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
		ppd->tp_status = TP_STATUS_VLAN_VALID;
	} else {
		ppd->hv1.tp_vlan_tci = ppd->tp_status = 0;
	}
}

862
static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
863 864 865 866 867 868 869 870 871 872
			struct tpacket3_hdr *ppd)
{
	prb_fill_vlan_info(pkc, ppd);

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

873
static void prb_fill_curr_block(char *curr,
874 875
				struct tpacket_kbdq_core *pkc,
				struct tpacket_block_desc *pbd,
876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896
				unsigned int len)
{
	struct tpacket3_hdr *ppd;

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

/* Assumes caller has the sk->rx_queue.lock */
static void *__packet_lookup_frame_in_block(struct packet_sock *po,
					    struct sk_buff *skb,
						int status,
					    unsigned int len
					    )
{
897 898
	struct tpacket_kbdq_core *pkc;
	struct tpacket_block_desc *pbd;
899 900
	char *curr, *end;

J
Joe Perches 已提交
901
	pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926
	pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);

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

	smp_mb();
	curr = pkc->nxt_offset;
	pkc->skb = skb;
J
Joe Perches 已提交
927
	end = (char *)pbd + pkc->kblk_size;
928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952

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

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

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

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

953
static void *packet_current_rx_frame(struct packet_sock *po,
954 955 956 957 958 959 960 961 962 963 964 965 966 967 968
					    struct sk_buff *skb,
					    int status, unsigned int len)
{
	char *curr = NULL;
	switch (po->tp_version) {
	case TPACKET_V1:
	case TPACKET_V2:
		curr = packet_lookup_frame(po, &po->rx_ring,
					po->rx_ring.head, status);
		return curr;
	case TPACKET_V3:
		return __packet_lookup_frame_in_block(po, skb, status, len);
	default:
		WARN(1, "TPACKET version not supported\n");
		BUG();
969
		return NULL;
970 971 972
	}
}

973
static void *prb_lookup_block(struct packet_sock *po,
974 975 976 977
				     struct packet_ring_buffer *rb,
				     unsigned int previous,
				     int status)
{
978 979
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
	struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, previous);
980 981 982 983 984 985

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

986
static int prb_previous_blk_num(struct packet_ring_buffer *rb)
987 988 989 990 991 992 993 994 995 996
{
	unsigned int prev;
	if (rb->prb_bdqc.kactive_blk_num)
		prev = rb->prb_bdqc.kactive_blk_num-1;
	else
		prev = rb->prb_bdqc.knum_blocks-1;
	return prev;
}

/* Assumes caller has held the rx_queue.lock */
997
static void *__prb_previous_block(struct packet_sock *po,
998 999 1000 1001 1002 1003 1004
					 struct packet_ring_buffer *rb,
					 int status)
{
	unsigned int previous = prb_previous_blk_num(rb);
	return prb_lookup_block(po, rb, previous, status);
}

1005
static void *packet_previous_rx_frame(struct packet_sock *po,
1006 1007 1008 1009 1010 1011 1012 1013 1014
					     struct packet_ring_buffer *rb,
					     int status)
{
	if (po->tp_version <= TPACKET_V2)
		return packet_previous_frame(po, rb, status);

	return __prb_previous_block(po, rb, status);
}

1015
static void packet_increment_rx_head(struct packet_sock *po,
1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029
					    struct packet_ring_buffer *rb)
{
	switch (po->tp_version) {
	case TPACKET_V1:
	case TPACKET_V2:
		return packet_increment_head(rb);
	case TPACKET_V3:
	default:
		WARN(1, "TPACKET version not supported.\n");
		BUG();
		return;
	}
}

1030
static void *packet_previous_frame(struct packet_sock *po,
J
Johann Baudy 已提交
1031 1032 1033 1034 1035 1036 1037
		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);
}

1038
static void packet_increment_head(struct packet_ring_buffer *buff)
J
Johann Baudy 已提交
1039 1040 1041 1042
{
	buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}

L
Linus Torvalds 已提交
1043 1044
static void packet_sock_destruct(struct sock *sk)
{
1045 1046
	skb_queue_purge(&sk->sk_error_queue);

1047 1048
	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
L
Linus Torvalds 已提交
1049 1050

	if (!sock_flag(sk, SOCK_DEAD)) {
E
Eric Dumazet 已提交
1051
		pr_err("Attempt to release alive packet socket: %p\n", sk);
L
Linus Torvalds 已提交
1052 1053 1054
		return;
	}

1055
	sk_refcnt_debug_dec(sk);
L
Linus Torvalds 已提交
1056 1057
}

D
David S. Miller 已提交
1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087
static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
{
	int x = atomic_read(&f->rr_cur) + 1;

	if (x >= num)
		x = 0;

	return x;
}

static struct sock *fanout_demux_hash(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
{
	u32 idx, hash = skb->rxhash;

	idx = ((u64)hash * num) >> 32;

	return f->arr[idx];
}

static struct sock *fanout_demux_lb(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
{
	int cur, old;

	cur = atomic_read(&f->rr_cur);
	while ((old = atomic_cmpxchg(&f->rr_cur, cur,
				     fanout_rr_next(f, num))) != cur)
		cur = old;
	return f->arr[cur];
}

1088 1089 1090 1091 1092 1093 1094 1095 1096
static struct sock *fanout_demux_cpu(struct packet_fanout *f, struct sk_buff *skb, unsigned int num)
{
	unsigned int cpu = smp_processor_id();

	return f->arr[cpu % num];
}

static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
			     struct packet_type *pt, struct net_device *orig_dev)
D
David S. Miller 已提交
1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
{
	struct packet_fanout *f = pt->af_packet_priv;
	unsigned int num = f->num_members;
	struct packet_sock *po;
	struct sock *sk;

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

1109 1110 1111 1112
	switch (f->type) {
	case PACKET_FANOUT_HASH:
	default:
		if (f->defrag) {
1113
			skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125
			if (!skb)
				return 0;
		}
		skb_get_rxhash(skb);
		sk = fanout_demux_hash(f, skb, num);
		break;
	case PACKET_FANOUT_LB:
		sk = fanout_demux_lb(f, skb, num);
		break;
	case PACKET_FANOUT_CPU:
		sk = fanout_demux_cpu(f, skb, num);
		break;
D
David S. Miller 已提交
1126 1127 1128 1129 1130 1131 1132
	}

	po = pkt_sk(sk);

	return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
}

1133 1134
DEFINE_MUTEX(fanout_mutex);
EXPORT_SYMBOL_GPL(fanout_mutex);
D
David S. Miller 已提交
1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163
static LIST_HEAD(fanout_list);

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

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

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

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

1164 1165 1166 1167 1168 1169 1170 1171
bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
{
	if (ptype->af_packet_priv == (void*)((struct packet_sock *)sk)->fanout)
		return true;

	return false;
}

1172
static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
D
David S. Miller 已提交
1173 1174 1175
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_fanout *f, *match;
1176 1177
	u8 type = type_flags & 0xff;
	u8 defrag = (type_flags & PACKET_FANOUT_FLAG_DEFRAG) ? 1 : 0;
D
David S. Miller 已提交
1178 1179 1180 1181 1182
	int err;

	switch (type) {
	case PACKET_FANOUT_HASH:
	case PACKET_FANOUT_LB:
1183
	case PACKET_FANOUT_CPU:
D
David S. Miller 已提交
1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203
		break;
	default:
		return -EINVAL;
	}

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

	if (po->fanout)
		return -EALREADY;

	mutex_lock(&fanout_mutex);
	match = NULL;
	list_for_each_entry(f, &fanout_list, list) {
		if (f->id == id &&
		    read_pnet(&f->net) == sock_net(sk)) {
			match = f;
			break;
		}
	}
E
Eric Dumazet 已提交
1204
	err = -EINVAL;
1205
	if (match && match->defrag != defrag)
E
Eric Dumazet 已提交
1206
		goto out;
D
David S. Miller 已提交
1207
	if (!match) {
E
Eric Dumazet 已提交
1208
		err = -ENOMEM;
D
David S. Miller 已提交
1209
		match = kzalloc(sizeof(*match), GFP_KERNEL);
E
Eric Dumazet 已提交
1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223
		if (!match)
			goto out;
		write_pnet(&match->net, sock_net(sk));
		match->id = id;
		match->type = type;
		match->defrag = defrag;
		atomic_set(&match->rr_cur, 0);
		INIT_LIST_HEAD(&match->list);
		spin_lock_init(&match->lock);
		atomic_set(&match->sk_ref, 0);
		match->prot_hook.type = po->prot_hook.type;
		match->prot_hook.dev = po->prot_hook.dev;
		match->prot_hook.func = packet_rcv_fanout;
		match->prot_hook.af_packet_priv = match;
1224
		match->prot_hook.id_match = match_fanout_group;
E
Eric Dumazet 已提交
1225 1226
		dev_add_pack(&match->prot_hook);
		list_add(&match->list, &fanout_list);
D
David S. Miller 已提交
1227
	}
E
Eric Dumazet 已提交
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238
	err = -EINVAL;
	if (match->type == type &&
	    match->prot_hook.type == po->prot_hook.type &&
	    match->prot_hook.dev == po->prot_hook.dev) {
		err = -ENOSPC;
		if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
			__dev_remove_pack(&po->prot_hook);
			po->fanout = match;
			atomic_inc(&match->sk_ref);
			__fanout_link(sk, po);
			err = 0;
D
David S. Miller 已提交
1239 1240
		}
	}
E
Eric Dumazet 已提交
1241
out:
D
David S. Miller 已提交
1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254
	mutex_unlock(&fanout_mutex);
	return err;
}

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

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

1255
	mutex_lock(&fanout_mutex);
D
David S. Miller 已提交
1256 1257 1258 1259 1260 1261 1262 1263 1264
	po->fanout = NULL;

	if (atomic_dec_and_test(&f->sk_ref)) {
		list_del(&f->list);
		dev_remove_pack(&f->prot_hook);
		kfree(f);
	}
	mutex_unlock(&fanout_mutex);
}
L
Linus Torvalds 已提交
1265

1266
static const struct proto_ops packet_ops;
L
Linus Torvalds 已提交
1267

1268
static const struct proto_ops packet_ops_spkt;
L
Linus Torvalds 已提交
1269

E
Eric Dumazet 已提交
1270 1271
static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
1272 1273 1274 1275 1276 1277 1278 1279 1280 1281
{
	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;
1282

L
Linus Torvalds 已提交
1283 1284 1285 1286 1287 1288 1289
	/*
	 *	Yank back the headers [hope the device set this
	 *	right or kerboom...]
	 *
	 *	Incoming packets have ll header pulled,
	 *	push it back.
	 *
1290
	 *	For outgoing ones skb->data == skb_mac_header(skb)
L
Linus Torvalds 已提交
1291 1292 1293 1294 1295 1296
	 *	so that this procedure is noop.
	 */

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

O
Octavian Purdila 已提交
1297
	if (!net_eq(dev_net(dev), sock_net(sk)))
1298 1299
		goto out;

E
Eric Dumazet 已提交
1300 1301
	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL)
L
Linus Torvalds 已提交
1302 1303 1304
		goto oom;

	/* drop any routing info */
E
Eric Dumazet 已提交
1305
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1306

1307 1308 1309
	/* drop conntrack reference */
	nf_reset(skb);

1310
	spkt = &PACKET_SKB_CB(skb)->sa.pkt;
L
Linus Torvalds 已提交
1311

1312
	skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326

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

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

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

E
Eric Dumazet 已提交
1327
	if (sock_queue_rcv_skb(sk, skb) == 0)
L
Linus Torvalds 已提交
1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340
		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
 */
1341

L
Linus Torvalds 已提交
1342 1343 1344 1345
static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
			       struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
1346
	struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1347
	struct sk_buff *skb = NULL;
L
Linus Torvalds 已提交
1348
	struct net_device *dev;
E
Eric Dumazet 已提交
1349
	__be16 proto = 0;
L
Linus Torvalds 已提交
1350
	int err;
1351
	int extra_len = 0;
1352

L
Linus Torvalds 已提交
1353
	/*
1354
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1355 1356
	 */

E
Eric Dumazet 已提交
1357
	if (saddr) {
L
Linus Torvalds 已提交
1358
		if (msg->msg_namelen < sizeof(struct sockaddr))
E
Eric Dumazet 已提交
1359 1360 1361 1362 1363
			return -EINVAL;
		if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
			proto = saddr->spkt_protocol;
	} else
		return -ENOTCONN;	/* SOCK_PACKET must be sent giving an address */
L
Linus Torvalds 已提交
1364 1365

	/*
1366
	 *	Find the device first to size check it
L
Linus Torvalds 已提交
1367 1368
	 */

1369
	saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1370
retry:
E
Eric Dumazet 已提交
1371 1372
	rcu_read_lock();
	dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
L
Linus Torvalds 已提交
1373 1374 1375
	err = -ENODEV;
	if (dev == NULL)
		goto out_unlock;
1376

1377 1378 1379 1380
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

L
Linus Torvalds 已提交
1381
	/*
E
Eric Dumazet 已提交
1382 1383
	 * You may not queue a frame bigger than the mtu. This is the lowest level
	 * raw protocol and you must do your own fragmentation at this level.
L
Linus Torvalds 已提交
1384
	 */
1385

1386 1387 1388 1389 1390 1391 1392 1393
	if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
		if (!netif_supports_nofcs(dev)) {
			err = -EPROTONOSUPPORT;
			goto out_unlock;
		}
		extra_len = 4; /* We're doing our own CRC */
	}

L
Linus Torvalds 已提交
1394
	err = -EMSGSIZE;
1395
	if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
L
Linus Torvalds 已提交
1396 1397
		goto out_unlock;

1398 1399
	if (!skb) {
		size_t reserved = LL_RESERVED_SPACE(dev);
1400
		int tlen = dev->needed_tailroom;
1401 1402 1403
		unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;

		rcu_read_unlock();
1404
		skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424
		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;
L
Linus Torvalds 已提交
1425 1426
	}

1427
	if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439
		/* 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;
		}
	}
1440

L
Linus Torvalds 已提交
1441 1442 1443
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1444
	skb->mark = sk->sk_mark;
1445
	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1446 1447
	if (err < 0)
		goto out_unlock;
L
Linus Torvalds 已提交
1448

1449 1450 1451
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

L
Linus Torvalds 已提交
1452
	dev_queue_xmit(skb);
E
Eric Dumazet 已提交
1453
	rcu_read_unlock();
E
Eric Dumazet 已提交
1454
	return len;
L
Linus Torvalds 已提交
1455 1456

out_unlock:
E
Eric Dumazet 已提交
1457
	rcu_read_unlock();
1458 1459
out_free:
	kfree_skb(skb);
L
Linus Torvalds 已提交
1460 1461 1462
	return err;
}

1463
static unsigned int run_filter(const struct sk_buff *skb,
E
Eric Dumazet 已提交
1464
				      const struct sock *sk,
D
David S. Miller 已提交
1465
				      unsigned int res)
L
Linus Torvalds 已提交
1466 1467
{
	struct sk_filter *filter;
1468

1469 1470
	rcu_read_lock();
	filter = rcu_dereference(sk->sk_filter);
D
David S. Miller 已提交
1471
	if (filter != NULL)
1472
		res = SK_RUN_FILTER(filter, skb);
1473
	rcu_read_unlock();
L
Linus Torvalds 已提交
1474

D
David S. Miller 已提交
1475
	return res;
L
Linus Torvalds 已提交
1476 1477 1478
}

/*
E
Eric Dumazet 已提交
1479 1480 1481 1482 1483 1484 1485 1486 1487
 * This function makes lazy skb cloning in hope that most of packets
 * are discarded by BPF.
 *
 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
 * and skb->cb are mangled. It works because (and until) packets
 * falling here are owned by current CPU. Output packets are cloned
 * by dev_queue_xmit_nit(), input packets are processed by net_bh
 * sequencially, so that if we return skb to original state on exit,
 * we will not harm anyone.
L
Linus Torvalds 已提交
1488 1489
 */

E
Eric Dumazet 已提交
1490 1491
static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
		      struct packet_type *pt, struct net_device *orig_dev)
L
Linus Torvalds 已提交
1492 1493 1494 1495
{
	struct sock *sk;
	struct sockaddr_ll *sll;
	struct packet_sock *po;
E
Eric Dumazet 已提交
1496
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
1497
	int skb_len = skb->len;
D
David S. Miller 已提交
1498
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
1499 1500 1501 1502 1503 1504 1505

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

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

O
Octavian Purdila 已提交
1506
	if (!net_eq(dev_net(dev), sock_net(sk)))
1507 1508
		goto drop;

L
Linus Torvalds 已提交
1509 1510
	skb->dev = dev;

1511
	if (dev->header_ops) {
L
Linus Torvalds 已提交
1512
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
1513 1514 1515 1516 1517
		 * 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
1518 1519
		 */
		if (sk->sk_type != SOCK_DGRAM)
1520
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1521 1522
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
1523
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1524 1525 1526 1527 1528
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
1529 1530
	res = run_filter(skb, sk, snaplen);
	if (!res)
1531
		goto drop_n_restore;
D
David S. Miller 已提交
1532 1533
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
1534

E
Eric Dumazet 已提交
1535
	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
L
Linus Torvalds 已提交
1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546
		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;
		}
1547
		consume_skb(skb);
L
Linus Torvalds 已提交
1548 1549 1550
		skb = nskb;
	}

1551 1552 1553 1554
	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
1555 1556 1557 1558
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
1559
	if (unlikely(po->origdev))
1560 1561 1562
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
1563

S
Stephen Hemminger 已提交
1564
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
1565

1566
	PACKET_SKB_CB(skb)->origlen = skb->len;
1567

L
Linus Torvalds 已提交
1568 1569 1570 1571 1572
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
1573
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1574

1575 1576 1577
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
1578 1579
	spin_lock(&sk->sk_receive_queue.lock);
	po->stats.tp_packets++;
1580
	skb->dropcount = atomic_read(&sk->sk_drops);
L
Linus Torvalds 已提交
1581 1582 1583 1584 1585 1586
	__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:
1587 1588 1589 1590
	spin_lock(&sk->sk_receive_queue.lock);
	po->stats.tp_drops++;
	atomic_inc(&sk->sk_drops);
	spin_unlock(&sk->sk_receive_queue.lock);
L
Linus Torvalds 已提交
1591 1592 1593 1594 1595 1596 1597

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
1598
	consume_skb(skb);
L
Linus Torvalds 已提交
1599 1600 1601
	return 0;
}

E
Eric Dumazet 已提交
1602 1603
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
1604 1605 1606 1607
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
1608 1609 1610
	union {
		struct tpacket_hdr *h1;
		struct tpacket2_hdr *h2;
1611
		struct tpacket3_hdr *h3;
1612 1613
		void *raw;
	} h;
E
Eric Dumazet 已提交
1614
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
1615
	int skb_len = skb->len;
D
David S. Miller 已提交
1616
	unsigned int snaplen, res;
1617
	unsigned long status = TP_STATUS_USER;
1618
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
1619
	struct sk_buff *copy_skb = NULL;
1620
	struct timeval tv;
1621
	struct timespec ts;
1622
	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628 1629

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

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

O
Octavian Purdila 已提交
1630
	if (!net_eq(dev_net(dev), sock_net(sk)))
1631 1632
		goto drop;

1633
	if (dev->header_ops) {
L
Linus Torvalds 已提交
1634
		if (sk->sk_type != SOCK_DGRAM)
1635
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1636 1637
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
1638
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1639 1640 1641
		}
	}

1642 1643 1644
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;

L
Linus Torvalds 已提交
1645 1646
	snaplen = skb->len;

D
David S. Miller 已提交
1647 1648
	res = run_filter(skb, sk, snaplen);
	if (!res)
1649
		goto drop_n_restore;
D
David S. Miller 已提交
1650 1651
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
1652 1653

	if (sk->sk_type == SOCK_DGRAM) {
1654 1655
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
1656
	} else {
1657
		unsigned int maclen = skb_network_offset(skb);
1658
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
1659 1660
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
1661 1662
		macoff = netoff - maclen;
	}
1663 1664 1665
	if (po->tp_version <= TPACKET_V2) {
		if (macoff + snaplen > po->rx_ring.frame_size) {
			if (po->copy_thresh &&
E
Eric Dumazet 已提交
1666
			    atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1667 1668 1669 1670 1671 1672 1673 1674
				if (skb_shared(skb)) {
					copy_skb = skb_clone(skb, GFP_ATOMIC);
				} else {
					copy_skb = skb_get(skb);
					skb_head = skb->data;
				}
				if (copy_skb)
					skb_set_owner_r(copy_skb, sk);
L
Linus Torvalds 已提交
1675
			}
1676 1677 1678
			snaplen = po->rx_ring.frame_size - macoff;
			if ((int)snaplen < 0)
				snaplen = 0;
L
Linus Torvalds 已提交
1679 1680 1681
		}
	}
	spin_lock(&sk->sk_receive_queue.lock);
1682 1683
	h.raw = packet_current_rx_frame(po, skb,
					TP_STATUS_KERNEL, (macoff+snaplen));
1684
	if (!h.raw)
L
Linus Torvalds 已提交
1685
		goto ring_is_full;
1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696
	if (po->tp_version <= TPACKET_V2) {
		packet_increment_rx_head(po, &po->rx_ring);
	/*
	 * LOSING will be reported till you read the stats,
	 * because it's COR - Clear On Read.
	 * Anyways, moving it for V1/V2 only as V3 doesn't need this
	 * at packet level.
	 */
		if (po->stats.tp_drops)
			status |= TP_STATUS_LOSING;
	}
L
Linus Torvalds 已提交
1697 1698 1699 1700 1701 1702 1703
	po->stats.tp_packets++;
	if (copy_skb) {
		status |= TP_STATUS_COPY;
		__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
	}
	spin_unlock(&sk->sk_receive_queue.lock);

1704
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
L
Linus Torvalds 已提交
1705

1706 1707 1708 1709 1710 1711
	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;
1712 1713 1714 1715 1716 1717 1718
		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)
1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730
			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;
1731 1732 1733 1734 1735 1736 1737
		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)
1738 1739 1740 1741 1742
			ts = ktime_to_timespec(skb->tstamp);
		else
			getnstimeofday(&ts);
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
1743 1744 1745 1746 1747 1748
		if (vlan_tx_tag_present(skb)) {
			h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
			status |= TP_STATUS_VLAN_VALID;
		} else {
			h.h2->tp_vlan_tci = 0;
		}
1749
		h.h2->tp_padding = 0;
1750 1751
		hdrlen = sizeof(*h.h2);
		break;
1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774
	case TPACKET_V3:
		/* tp_nxt_offset,vlan are already populated above.
		 * So DONT clear those fields here
		 */
		h.h3->tp_status |= status;
		h.h3->tp_len = skb->len;
		h.h3->tp_snaplen = snaplen;
		h.h3->tp_mac = macoff;
		h.h3->tp_net = netoff;
		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)
			ts = ktime_to_timespec(skb->tstamp);
		else
			getnstimeofday(&ts);
		h.h3->tp_sec  = ts.tv_sec;
		h.h3->tp_nsec = ts.tv_nsec;
		hdrlen = sizeof(*h.h3);
		break;
1775 1776 1777
	default:
		BUG();
	}
L
Linus Torvalds 已提交
1778

1779
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
1780
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
1781 1782 1783 1784
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
1785
	if (unlikely(po->origdev))
1786 1787 1788
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
1789

R
Ralf Baechle 已提交
1790
	smp_mb();
1791
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
L
Linus Torvalds 已提交
1792
	{
1793 1794
		u8 *start, *end;

1795 1796 1797 1798 1799 1800
		if (po->tp_version <= TPACKET_V2) {
			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));
		}
1801
		smp_wmb();
L
Linus Torvalds 已提交
1802
	}
1803
#endif
1804 1805 1806 1807
	if (po->tp_version <= TPACKET_V2)
		__packet_set_status(po, h.raw, status);
	else
		prb_clear_blk_fill_status(&po->rx_ring);
L
Linus Torvalds 已提交
1808 1809 1810 1811 1812 1813 1814 1815 1816

	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:
1817
	kfree_skb(skb);
L
Linus Torvalds 已提交
1818 1819 1820 1821 1822 1823 1824
	return 0;

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

	sk->sk_data_ready(sk, 0);
1825
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
1826 1827 1828
	goto drop_n_restore;
}

J
Johann Baudy 已提交
1829 1830 1831
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
E
Eric Dumazet 已提交
1832
	void *ph;
L
Linus Torvalds 已提交
1833

J
Johann Baudy 已提交
1834 1835 1836 1837 1838 1839 1840 1841 1842 1843
	if (likely(po->tx_ring.pg_vec)) {
		ph = skb_shinfo(skb)->destructor_arg;
		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
1844 1845
static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
		void *frame, struct net_device *dev, int size_max,
1846
		__be16 proto, unsigned char *addr, int hlen)
J
Johann Baudy 已提交
1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863
{
	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;
1864
	skb->mark = po->sk.sk_mark;
J
Johann Baudy 已提交
1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875
	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
1876
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
J
Johann Baudy 已提交
1877 1878 1879
		return -EMSGSIZE;
	}

1880
	skb_reserve(skb, hlen);
J
Johann Baudy 已提交
1881 1882 1883 1884 1885 1886 1887 1888 1889 1890
	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
1891
	} else if (dev->hard_header_len) {
J
Johann Baudy 已提交
1892 1893
		/* net device doesn't like empty head */
		if (unlikely(tp_len <= dev->hard_header_len)) {
E
Eric Dumazet 已提交
1894 1895
			pr_err("packet size is too short (%d < %d)\n",
			       tp_len, dev->hard_header_len);
J
Johann Baudy 已提交
1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922
			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
1923 1924
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
1925 1926 1927
			return -EFAULT;
		}

1928 1929
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
1930 1931
		flush_dcache_page(page);
		get_page(page);
1932
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946
		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;
1947 1948
	bool need_rls_dev = false;
	int err, reserve = 0;
E
Eric Dumazet 已提交
1949 1950
	void *ph;
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
J
Johann Baudy 已提交
1951 1952 1953 1954
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
	int status = 0;
1955
	int hlen, tlen;
J
Johann Baudy 已提交
1956 1957 1958 1959 1960

	mutex_lock(&po->pg_vec_lock);

	err = -EBUSY;
	if (saddr == NULL) {
1961
		dev = po->prot_hook.dev;
J
Johann Baudy 已提交
1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
		if (msg->msg_namelen < (saddr->sll_halen
					+ offsetof(struct sockaddr_ll,
						sll_addr)))
			goto out;
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
1974 1975
		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
		need_rls_dev = true;
J
Johann Baudy 已提交
1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988
	}

	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
1989
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

	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;
2004 2005
		hlen = LL_RESERVED_SPACE(dev);
		tlen = dev->needed_tailroom;
J
Johann Baudy 已提交
2006
		skb = sock_alloc_send_skb(&po->sk,
2007
				hlen + tlen + sizeof(struct sockaddr_ll),
J
Johann Baudy 已提交
2008 2009 2010 2011 2012 2013
				0, &err);

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

		tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2014
				addr, hlen);
J
Johann Baudy 已提交
2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035

		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);
2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049
		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
2050 2051
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
2052 2053 2054 2055
	} while (likely((ph != NULL) ||
			((!(msg->msg_flags & MSG_DONTWAIT)) &&
			 (atomic_read(&po->tx_ring.pending))))
		);
J
Johann Baudy 已提交
2056 2057 2058 2059 2060 2061 2062 2063

	err = len_sum;
	goto out_put;

out_status:
	__packet_set_status(po, ph, status);
	kfree_skb(skb);
out_put:
2064 2065
	if (need_rls_dev)
		dev_put(dev);
J
Johann Baudy 已提交
2066 2067 2068 2069 2070
out:
	mutex_unlock(&po->pg_vec_lock);
	return err;
}

2071 2072 2073 2074
static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
				        size_t reserve, size_t len,
				        size_t linear, int noblock,
				        int *err)
2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094
{
	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
2095
static int packet_snd(struct socket *sock,
L
Linus Torvalds 已提交
2096 2097 2098
			  struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
2099
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
L
Linus Torvalds 已提交
2100 2101
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
2102
	__be16 proto;
2103
	bool need_rls_dev = false;
L
Linus Torvalds 已提交
2104
	unsigned char *addr;
2105
	int err, reserve = 0;
2106 2107 2108 2109 2110
	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;
2111
	int hlen, tlen;
2112
	int extra_len = 0;
L
Linus Torvalds 已提交
2113 2114

	/*
2115
	 *	Get and verify the address.
L
Linus Torvalds 已提交
2116
	 */
2117

L
Linus Torvalds 已提交
2118
	if (saddr == NULL) {
2119
		dev = po->prot_hook.dev;
L
Linus Torvalds 已提交
2120 2121 2122 2123 2124 2125
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
2126 2127
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
2128 2129
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
2130 2131
		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
		need_rls_dev = true;
L
Linus Torvalds 已提交
2132 2133 2134 2135 2136 2137 2138 2139
	}

	err = -ENXIO;
	if (dev == NULL)
		goto out_unlock;
	if (sock->type == SOCK_RAW)
		reserve = dev->hard_header_len;

2140 2141 2142 2143
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191
	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;

		}
	}

2192 2193 2194 2195 2196 2197 2198 2199
	if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
		if (!netif_supports_nofcs(dev)) {
			err = -EPROTONOSUPPORT;
			goto out_unlock;
		}
		extra_len = 4; /* We're doing our own CRC */
	}

L
Linus Torvalds 已提交
2200
	err = -EMSGSIZE;
2201
	if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
L
Linus Torvalds 已提交
2202 2203
		goto out_unlock;

2204
	err = -ENOBUFS;
2205 2206 2207
	hlen = LL_RESERVED_SPACE(dev);
	tlen = dev->needed_tailroom;
	skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2208
			       msg->msg_flags & MSG_DONTWAIT, &err);
E
Eric Dumazet 已提交
2209
	if (skb == NULL)
L
Linus Torvalds 已提交
2210 2211
		goto out_unlock;

2212
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
2213

2214 2215
	err = -EINVAL;
	if (sock->type == SOCK_DGRAM &&
2216
	    (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2217
		goto out_free;
L
Linus Torvalds 已提交
2218 2219

	/* Returns -EFAULT on error */
2220
	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
L
Linus Torvalds 已提交
2221 2222
	if (err)
		goto out_free;
2223
	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2224 2225
	if (err < 0)
		goto out_free;
L
Linus Torvalds 已提交
2226

2227
	if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240
		/* 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
2241 2242 2243
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
2244
	skb->mark = sk->sk_mark;
L
Linus Torvalds 已提交
2245

2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264
	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;
	}

2265 2266 2267
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

L
Linus Torvalds 已提交
2268 2269 2270 2271 2272 2273 2274 2275
	/*
	 *	Now send it
	 */

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

2276 2277
	if (need_rls_dev)
		dev_put(dev);
L
Linus Torvalds 已提交
2278

E
Eric Dumazet 已提交
2279
	return len;
L
Linus Torvalds 已提交
2280 2281 2282 2283

out_free:
	kfree_skb(skb);
out_unlock:
2284
	if (dev && need_rls_dev)
L
Linus Torvalds 已提交
2285 2286 2287 2288 2289
		dev_put(dev);
out:
	return err;
}

J
Johann Baudy 已提交
2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300
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
2301 2302 2303 2304 2305 2306 2307 2308 2309
/*
 *	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;
2310
	struct net *net;
2311
	union tpacket_req_u req_u;
L
Linus Torvalds 已提交
2312 2313 2314 2315

	if (!sk)
		return 0;

2316
	net = sock_net(sk);
L
Linus Torvalds 已提交
2317 2318
	po = pkt_sk(sk);

2319 2320
	spin_lock_bh(&net->packet.sklist_lock);
	sk_del_node_init_rcu(sk);
2321
	sock_prot_inuse_add(net, sk->sk_prot, -1);
2322
	spin_unlock_bh(&net->packet.sklist_lock);
L
Linus Torvalds 已提交
2323

2324
	spin_lock(&po->bind_lock);
2325
	unregister_prot_hook(sk, false);
2326 2327 2328 2329
	if (po->prot_hook.dev) {
		dev_put(po->prot_hook.dev);
		po->prot_hook.dev = NULL;
	}
2330
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
2331 2332 2333

	packet_flush_mclist(sk);

2334
	memset(&req_u, 0, sizeof(req_u));
J
Johann Baudy 已提交
2335 2336

	if (po->rx_ring.pg_vec)
2337
		packet_set_ring(sk, &req_u, 1, 0);
J
Johann Baudy 已提交
2338 2339

	if (po->tx_ring.pg_vec)
2340
		packet_set_ring(sk, &req_u, 1, 1);
L
Linus Torvalds 已提交
2341

D
David S. Miller 已提交
2342 2343
	fanout_release(sk);

2344
	synchronize_net();
L
Linus Torvalds 已提交
2345 2346 2347 2348 2349 2350 2351 2352 2353
	/*
	 *	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);
2354
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
2355 2356 2357 2358 2359 2360 2361 2362 2363

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

A
Al Viro 已提交
2364
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
L
Linus Torvalds 已提交
2365 2366
{
	struct packet_sock *po = pkt_sk(sk);
D
David S. Miller 已提交
2367

2368 2369 2370 2371
	if (po->fanout) {
		if (dev)
			dev_put(dev);

D
David S. Miller 已提交
2372
		return -EINVAL;
2373
	}
L
Linus Torvalds 已提交
2374 2375 2376 2377

	lock_sock(sk);

	spin_lock(&po->bind_lock);
2378
	unregister_prot_hook(sk, true);
L
Linus Torvalds 已提交
2379 2380
	po->num = protocol;
	po->prot_hook.type = protocol;
2381 2382
	if (po->prot_hook.dev)
		dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
2383 2384 2385 2386 2387 2388 2389
	po->prot_hook.dev = dev;

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

	if (protocol == 0)
		goto out_unlock;

2390
	if (!dev || (dev->flags & IFF_UP)) {
2391
		register_prot_hook(sk);
2392 2393 2394 2395
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407
	}

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
2408 2409
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
2410
{
E
Eric Dumazet 已提交
2411
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2412 2413 2414
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
2415

L
Linus Torvalds 已提交
2416 2417 2418
	/*
	 *	Check legality
	 */
2419

2420
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
2421
		return -EINVAL;
E
Eric Dumazet 已提交
2422
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
2423

2424
	dev = dev_get_by_name(sock_net(sk), name);
2425
	if (dev)
L
Linus Torvalds 已提交
2426 2427 2428 2429 2430 2431
		err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
	return err;
}

static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
E
Eric Dumazet 已提交
2432 2433
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2434 2435 2436 2437 2438 2439 2440
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
2441

L
Linus Torvalds 已提交
2442 2443 2444 2445 2446 2447 2448
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
2449
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465
		if (dev == NULL)
			goto out;
	}
	err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);

out:
	return err;
}

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

/*
2466
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
2467 2468
 */

2469 2470
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
2471 2472 2473
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
2474
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
2475 2476 2477 2478
	int err;

	if (!capable(CAP_NET_RAW))
		return -EPERM;
2479 2480
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
2481 2482 2483 2484 2485
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
2486
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
L
Linus Torvalds 已提交
2487 2488 2489 2490 2491 2492
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
2493

L
Linus Torvalds 已提交
2494 2495 2496 2497
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
2498
	po->num = proto;
L
Linus Torvalds 已提交
2499 2500

	sk->sk_destruct = packet_sock_destruct;
2501
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
2502 2503 2504 2505 2506 2507

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
2508
	mutex_init(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2509
	po->prot_hook.func = packet_rcv;
2510

L
Linus Torvalds 已提交
2511 2512
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
2513

L
Linus Torvalds 已提交
2514 2515
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
2516 2517
	if (proto) {
		po->prot_hook.type = proto;
2518
		register_prot_hook(sk);
L
Linus Torvalds 已提交
2519 2520
	}

2521 2522
	spin_lock_bh(&net->packet.sklist_lock);
	sk_add_node_rcu(sk, &net->packet.sklist);
2523
	sock_prot_inuse_add(net, &packet_proto, 1);
2524 2525
	spin_unlock_bh(&net->packet.sklist_lock);

E
Eric Dumazet 已提交
2526
	return 0;
L
Linus Torvalds 已提交
2527 2528 2529 2530
out:
	return err;
}

2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575
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
2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586
/*
 *	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;
2587
	struct sockaddr_ll *sll;
2588
	int vnet_hdr_len = 0;
L
Linus Torvalds 已提交
2589 2590

	err = -EINVAL;
2591
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
2592 2593 2594 2595 2596 2597 2598 2599
		goto out;

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

2600 2601 2602 2603 2604
	if (flags & MSG_ERRQUEUE) {
		err = packet_recv_error(sk, msg, len);
		goto out;
	}

L
Linus Torvalds 已提交
2605 2606 2607 2608 2609 2610 2611 2612 2613
	/*
	 *	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
2614
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
2615 2616

	/*
2617
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
2618 2619 2620 2621
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

2622
	if (skb == NULL)
L
Linus Torvalds 已提交
2623 2624
		goto out;

2625 2626 2627 2628 2629
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
2630
		if (len < vnet_hdr_len)
2631 2632
			goto out_free;

2633 2634
		len -= vnet_hdr_len;

2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657
		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;
2658
			vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2659
			vnet_hdr.csum_offset = skb->csum_offset;
2660 2661
		} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
			vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2662 2663 2664 2665 2666 2667 2668 2669
		} /* else everything is zero */

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

2670 2671 2672 2673 2674
	/*
	 *	If the address length field is there to be filled in, we fill
	 *	it in now.
	 */

2675
	sll = &PACKET_SKB_CB(skb)->sa.ll;
2676 2677 2678 2679 2680
	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
2681 2682 2683 2684 2685 2686
	/*
	 *	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
2687 2688 2689
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
2690 2691 2692 2693 2694 2695
	}

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

2696
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
2697 2698

	if (msg->msg_name)
2699 2700
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
L
Linus Torvalds 已提交
2701

2702
	if (pkt_sk(sk)->auxdata) {
2703 2704 2705 2706 2707 2708 2709 2710
		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;
2711
		aux.tp_net = skb_network_offset(skb);
2712 2713 2714 2715 2716 2717
		if (vlan_tx_tag_present(skb)) {
			aux.tp_vlan_tci = vlan_tx_tag_get(skb);
			aux.tp_status |= TP_STATUS_VLAN_VALID;
		} else {
			aux.tp_vlan_tci = 0;
		}
2718
		aux.tp_padding = 0;
2719
		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2720 2721
	}

L
Linus Torvalds 已提交
2722 2723 2724 2725
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
2726
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743

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
2744 2745 2746
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
2747
		strncpy(uaddr->sa_data, dev->name, 14);
E
Eric Dumazet 已提交
2748
	else
L
Linus Torvalds 已提交
2749
		memset(uaddr->sa_data, 0, 14);
E
Eric Dumazet 已提交
2750
	rcu_read_unlock();
L
Linus Torvalds 已提交
2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
	*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);
2762
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
2763 2764 2765 2766 2767 2768 2769

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
2770
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
2771 2772
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
2773 2774 2775 2776 2777 2778 2779 2780
	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
2781
	rcu_read_unlock();
2782
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
2783 2784 2785 2786

	return 0;
}

2787 2788
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
2789 2790 2791
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
2792 2793
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
2794
		if (what > 0)
2795
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
2796
		else
2797
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
2798 2799
		break;
	case PACKET_MR_PROMISC:
2800
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
2801 2802
		break;
	case PACKET_MR_ALLMULTI:
2803
		return dev_set_allmulti(dev, what);
L
Linus Torvalds 已提交
2804
		break;
2805
	case PACKET_MR_UNICAST:
2806 2807
		if (i->alen != dev->addr_len)
			return -EINVAL;
2808
		if (what > 0)
2809
			return dev_uc_add(dev, i->addr);
2810
		else
2811
			return dev_uc_del(dev, i->addr);
2812
		break;
E
Eric Dumazet 已提交
2813 2814
	default:
		break;
L
Linus Torvalds 已提交
2815
	}
2816
	return 0;
L
Linus Torvalds 已提交
2817 2818 2819 2820
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
E
Eric Dumazet 已提交
2821
	for ( ; i; i = i->next) {
L
Linus Torvalds 已提交
2822 2823 2824 2825 2826
		if (i->ifindex == dev->ifindex)
			packet_dev_mc(dev, i, what);
	}
}

2827
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
2828 2829 2830 2831 2832 2833 2834 2835 2836
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
2837
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
2838 2839 2840 2841
	if (!dev)
		goto done;

	err = -EINVAL;
2842
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
2843 2844 2845
		goto done;

	err = -ENOBUFS;
2846
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869
	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;
2870 2871 2872 2873 2874
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
2875 2876 2877 2878 2879 2880

done:
	rtnl_unlock();
	return err;
}

2881
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894
{
	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;
2895 2896
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
					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;
2921 2922
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
2923 2924 2925 2926 2927 2928 2929
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
2930
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
2931 2932
{
	struct sock *sk = sock->sk;
2933
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
2934 2935 2936 2937 2938
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
2939
	switch (optname) {
2940
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
2941 2942
	case PACKET_DROP_MEMBERSHIP:
	{
2943 2944 2945 2946
		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
2947
			return -EINVAL;
2948 2949
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
2950
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
2951
			return -EFAULT;
2952 2953
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
2954 2955 2956 2957 2958 2959
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
2960

L
Linus Torvalds 已提交
2961
	case PACKET_RX_RING:
J
Johann Baudy 已提交
2962
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
2963
	{
2964 2965
		union tpacket_req_u req_u;
		int len;
L
Linus Torvalds 已提交
2966

2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977
		switch (po->tp_version) {
		case TPACKET_V1:
		case TPACKET_V2:
			len = sizeof(req_u.req);
			break;
		case TPACKET_V3:
		default:
			len = sizeof(req_u.req3);
			break;
		}
		if (optlen < len)
L
Linus Torvalds 已提交
2978
			return -EINVAL;
2979 2980
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
2981
		if (copy_from_user(&req_u.req, optval, len))
L
Linus Torvalds 已提交
2982
			return -EFAULT;
2983 2984
		return packet_set_ring(sk, &req_u, 0,
			optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
2985 2986 2987 2988 2989
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
2990
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
2991
			return -EINVAL;
E
Eric Dumazet 已提交
2992
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
2993 2994 2995 2996 2997
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
2998 2999 3000 3001 3002 3003
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3004
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3005 3006 3007 3008 3009 3010
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
		case TPACKET_V2:
3011
		case TPACKET_V3:
3012 3013 3014 3015 3016 3017
			po->tp_version = val;
			return 0;
		default:
			return -EINVAL;
		}
	}
3018 3019 3020 3021 3022 3023
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3024
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3025 3026 3027 3028 3029 3030
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043
	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;
	}
3044 3045 3046 3047 3048 3049 3050 3051 3052 3053 3054 3055
	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;
	}
3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067
	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;
	}
3068 3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083
	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;
	}
3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095
	case PACKET_TIMESTAMP:
	{
		int val;

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

		po->tp_tstamp = val;
		return 0;
	}
D
David S. Miller 已提交
3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106
	case PACKET_FANOUT:
	{
		int val;

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

		return fanout_add(sk, val & 0xffff, val >> 16);
	}
L
Linus Torvalds 已提交
3107 3108 3109 3110 3111 3112 3113 3114 3115
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
3116
	int val, lv = sizeof(val);
L
Linus Torvalds 已提交
3117 3118
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
3119
	void *data = &val;
3120
	struct tpacket_stats st;
3121
	union tpacket_stats_u st_u;
L
Linus Torvalds 已提交
3122 3123 3124 3125

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

3126 3127
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
3128 3129 3130

	if (len < 0)
		return -EINVAL;
3131

J
Johann Baudy 已提交
3132
	switch (optname) {
L
Linus Torvalds 已提交
3133 3134
	case PACKET_STATISTICS:
		spin_lock_bh(&sk->sk_receive_queue.lock);
3135
		if (po->tp_version == TPACKET_V3) {
3136
			lv = sizeof(struct tpacket_stats_v3);
3137
			memcpy(&st_u.stats3, &po->stats,
3138
			       sizeof(struct tpacket_stats));
3139
			st_u.stats3.tp_freeze_q_cnt =
3140
					po->stats_u.stats3.tp_freeze_q_cnt;
3141 3142 3143
			st_u.stats3.tp_packets += po->stats.tp_drops;
			data = &st_u.stats3;
		} else {
3144
			lv = sizeof(struct tpacket_stats);
3145 3146 3147 3148
			st = po->stats;
			st.tp_packets += st.tp_drops;
			data = &st;
		}
L
Linus Torvalds 已提交
3149 3150
		memset(&po->stats, 0, sizeof(st));
		spin_unlock_bh(&sk->sk_receive_queue.lock);
3151 3152 3153
		break;
	case PACKET_AUXDATA:
		val = po->auxdata;
3154 3155 3156
		break;
	case PACKET_ORIGDEV:
		val = po->origdev;
3157 3158 3159
		break;
	case PACKET_VNET_HDR:
		val = po->has_vnet_hdr;
L
Linus Torvalds 已提交
3160
		break;
3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175
	case PACKET_VERSION:
		val = po->tp_version;
		break;
	case PACKET_HDRLEN:
		if (len > sizeof(int))
			len = sizeof(int);
		if (copy_from_user(&val, optval, len))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
			val = sizeof(struct tpacket_hdr);
			break;
		case TPACKET_V2:
			val = sizeof(struct tpacket2_hdr);
			break;
3176 3177 3178
		case TPACKET_V3:
			val = sizeof(struct tpacket3_hdr);
			break;
3179 3180 3181 3182
		default:
			return -EINVAL;
		}
		break;
3183 3184 3185
	case PACKET_RESERVE:
		val = po->tp_reserve;
		break;
J
Johann Baudy 已提交
3186 3187 3188
	case PACKET_LOSS:
		val = po->tp_loss;
		break;
3189 3190 3191
	case PACKET_TIMESTAMP:
		val = po->tp_tstamp;
		break;
D
David S. Miller 已提交
3192 3193 3194 3195 3196 3197
	case PACKET_FANOUT:
		val = (po->fanout ?
		       ((u32)po->fanout->id |
			((u32)po->fanout->type << 16)) :
		       0);
		break;
L
Linus Torvalds 已提交
3198 3199 3200 3201
	default:
		return -ENOPROTOOPT;
	}

3202 3203
	if (len > lv)
		len = lv;
3204 3205
	if (put_user(len, optlen))
		return -EFAULT;
3206 3207
	if (copy_to_user(optval, data, len))
		return -EFAULT;
3208
	return 0;
L
Linus Torvalds 已提交
3209 3210 3211 3212 3213 3214 3215
}


static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
{
	struct sock *sk;
	struct hlist_node *node;
3216
	struct net_device *dev = data;
3217
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
3218

3219 3220
	rcu_read_lock();
	sk_for_each_rcu(sk, node, &net->packet.sklist) {
L
Linus Torvalds 已提交
3221 3222 3223 3224 3225 3226
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
				packet_dev_mclist(dev, po->mclist, -1);
3227 3228
			/* fallthrough */

L
Linus Torvalds 已提交
3229 3230 3231 3232
		case NETDEV_DOWN:
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->running) {
3233
					__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
3234 3235 3236 3237 3238 3239
					sk->sk_err = ENETDOWN;
					if (!sock_flag(sk, SOCK_DEAD))
						sk->sk_error_report(sk);
				}
				if (msg == NETDEV_UNREGISTER) {
					po->ifindex = -1;
3240 3241
					if (po->prot_hook.dev)
						dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
3242 3243 3244 3245 3246 3247
					po->prot_hook.dev = NULL;
				}
				spin_unlock(&po->bind_lock);
			}
			break;
		case NETDEV_UP:
3248 3249
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
3250 3251
				if (po->num)
					register_prot_hook(sk);
3252
				spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
3253 3254 3255 3256
			}
			break;
		}
	}
3257
	rcu_read_unlock();
L
Linus Torvalds 已提交
3258 3259 3260 3261 3262 3263 3264 3265 3266
	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
3267
	switch (cmd) {
E
Eric Dumazet 已提交
3268 3269 3270
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
3271

E
Eric Dumazet 已提交
3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289
		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);
3290

L
Linus Torvalds 已提交
3291
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306
	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
3307 3308
#endif

E
Eric Dumazet 已提交
3309 3310
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
3311 3312 3313 3314
	}
	return 0;
}

E
Eric Dumazet 已提交
3315
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
3316 3317 3318 3319 3320 3321 3322
				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
3323
	if (po->rx_ring.pg_vec) {
3324 3325
		if (!packet_previous_rx_frame(po, &po->rx_ring,
			TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
3326 3327 3328
			mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
3329 3330 3331 3332 3333 3334
	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
3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345
	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
3346
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3347
	struct sock *sk = sock->sk;
3348

L
Linus Torvalds 已提交
3349 3350 3351 3352 3353 3354 3355
	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
3356
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3357
	struct sock *sk = sock->sk;
3358

L
Linus Torvalds 已提交
3359 3360 3361 3362
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

3363
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
3364 3365
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
3366 3367
};

3368 3369
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
3370 3371 3372
{
	int i;

3373
	for (i = 0; i < len; i++) {
3374
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
3375
			if (is_vmalloc_addr(pg_vec[i].buffer))
3376 3377 3378 3379 3380 3381
				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
3382 3383 3384 3385
	}
	kfree(pg_vec);
}

3386
static char *alloc_one_pg_vec_page(unsigned long order)
3387
{
3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399
	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
3400
	buffer = vzalloc((1 << order) * PAGE_SIZE);
3401

3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416
	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;
3417 3418
}

3419
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3420 3421
{
	unsigned int block_nr = req->tp_block_nr;
3422
	struct pgv *pg_vec;
3423 3424
	int i;

3425
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3426 3427 3428 3429
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
3430
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3431
		if (unlikely(!pg_vec[i].buffer))
3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442
			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
3443

3444
static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
J
Johann Baudy 已提交
3445
		int closing, int tx_ring)
L
Linus Torvalds 已提交
3446
{
3447
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
3448
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
3449
	int was_running, order = 0;
J
Johann Baudy 已提交
3450 3451
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
3452
	__be16 num;
3453 3454 3455 3456 3457 3458 3459 3460 3461
	int err = -EINVAL;
	/* Added to avoid minimal code churn */
	struct tpacket_req *req = &req_u->req;

	/* Opening a Tx-ring is NOT supported in TPACKET_V3 */
	if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
		WARN(1, "Tx-ring is not supported.\n");
		goto out;
	}
3462

J
Johann Baudy 已提交
3463 3464
	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
3465

J
Johann Baudy 已提交
3466 3467 3468 3469 3470 3471 3472
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
		if (atomic_read(&rb->pending))
			goto out;
	}
L
Linus Torvalds 已提交
3473

J
Johann Baudy 已提交
3474 3475 3476 3477 3478
	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
3479

3480 3481 3482 3483 3484 3485 3486
		switch (po->tp_version) {
		case TPACKET_V1:
			po->tp_hdrlen = TPACKET_HDRLEN;
			break;
		case TPACKET_V2:
			po->tp_hdrlen = TPACKET2_HDRLEN;
			break;
3487 3488 3489
		case TPACKET_V3:
			po->tp_hdrlen = TPACKET3_HDRLEN;
			break;
3490 3491
		}

J
Johann Baudy 已提交
3492
		err = -EINVAL;
3493
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
3494
			goto out;
3495
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
3496
			goto out;
3497
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
3498 3499
					po->tp_reserve))
			goto out;
3500
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
3501
			goto out;
L
Linus Torvalds 已提交
3502

J
Johann Baudy 已提交
3503 3504 3505 3506 3507 3508
		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
3509 3510

		err = -ENOMEM;
3511 3512 3513
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
3514
			goto out;
3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525
		switch (po->tp_version) {
		case TPACKET_V3:
		/* Transmit path is not supported. We checked
		 * it above but just being paranoid
		 */
			if (!tx_ring)
				init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
				break;
		default:
			break;
		}
J
Johann Baudy 已提交
3526 3527 3528 3529
	}
	/* Done */
	else {
		err = -EINVAL;
3530
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
3531
			goto out;
L
Linus Torvalds 已提交
3532 3533 3534 3535 3536 3537 3538 3539 3540 3541
	}

	lock_sock(sk);

	/* Detach socket from network */
	spin_lock(&po->bind_lock);
	was_running = po->running;
	num = po->num;
	if (was_running) {
		po->num = 0;
3542
		__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
3543 3544
	}
	spin_unlock(&po->bind_lock);
3545

L
Linus Torvalds 已提交
3546 3547 3548
	synchronize_net();

	err = -EBUSY;
3549
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3550 3551
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
3552
		spin_lock_bh(&rb_queue->lock);
3553
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
3554 3555 3556 3557 3558
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

3559 3560
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
3561 3562 3563 3564 3565

		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
3566
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
3567 3568
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
3569
	}
3570
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3571 3572

	spin_lock(&po->bind_lock);
3573
	if (was_running) {
L
Linus Torvalds 已提交
3574
		po->num = num;
3575
		register_prot_hook(sk);
L
Linus Torvalds 已提交
3576 3577
	}
	spin_unlock(&po->bind_lock);
3578 3579 3580 3581 3582
	if (closing && (po->tp_version > TPACKET_V2)) {
		/* Because we don't support block-based V3 on tx-ring */
		if (!tx_ring)
			prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
	}
L
Linus Torvalds 已提交
3583 3584 3585 3586 3587 3588 3589 3590
	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
3591 3592
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
3593 3594 3595
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
3596 3597
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
3598 3599 3600 3601 3602 3603 3604
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

3605
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616

	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
3617
		goto out;
J
Johann Baudy 已提交
3618 3619 3620

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
3621 3622 3623
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
3624 3625 3626 3627 3628
	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++) {
3629 3630
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
3631 3632
			int pg_num;

C
Changli Gao 已提交
3633 3634
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
3635 3636 3637 3638
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
3639
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
3640
			}
3641
		}
L
Linus Torvalds 已提交
3642
	}
J
Johann Baudy 已提交
3643

3644
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
3645 3646 3647 3648
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
3649
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3650 3651 3652
	return err;
}

3653
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673
	.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,
};

3674
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
3675 3676 3677 3678 3679 3680 3681
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
3682
	.getname =	packet_getname,
L
Linus Torvalds 已提交
3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694
	.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,
};

3695
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
3696 3697 3698 3699 3700 3701
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
3702
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
3703 3704 3705 3706 3707
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3708
	__acquires(RCU)
L
Linus Torvalds 已提交
3709
{
3710
	struct net *net = seq_file_net(seq);
3711 3712 3713

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
3714 3715 3716 3717
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
3718
	struct net *net = seq_file_net(seq);
3719
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
3720 3721 3722
}

static void packet_seq_stop(struct seq_file *seq, void *v)
3723
	__releases(RCU)
L
Linus Torvalds 已提交
3724
{
3725
	rcu_read_unlock();
L
Linus Torvalds 已提交
3726 3727
}

3728
static int packet_seq_show(struct seq_file *seq, void *v)
L
Linus Torvalds 已提交
3729 3730 3731 3732
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
3733
		struct sock *s = sk_entry(v);
L
Linus Torvalds 已提交
3734 3735 3736
		const struct packet_sock *po = pkt_sk(s);

		seq_printf(seq,
D
Dan Rosenberg 已提交
3737
			   "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
L
Linus Torvalds 已提交
3738 3739 3740 3741 3742 3743 3744 3745
			   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
3746
			   sock_i_ino(s));
L
Linus Torvalds 已提交
3747 3748 3749 3750 3751
	}

	return 0;
}

3752
static const struct seq_operations packet_seq_ops = {
L
Linus Torvalds 已提交
3753 3754 3755 3756 3757 3758 3759 3760
	.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)
{
3761 3762
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
3763 3764
}

3765
static const struct file_operations packet_seq_fops = {
L
Linus Torvalds 已提交
3766 3767 3768 3769
	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
3770
	.release	= seq_release_net,
L
Linus Torvalds 已提交
3771 3772 3773 3774
};

#endif

3775
static int __net_init packet_net_init(struct net *net)
3776
{
3777
	spin_lock_init(&net->packet.sklist_lock);
3778
	INIT_HLIST_HEAD(&net->packet.sklist);
3779 3780 3781 3782 3783 3784 3785

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

	return 0;
}

3786
static void __net_exit packet_net_exit(struct net *net)
3787 3788 3789 3790 3791 3792 3793 3794 3795 3796
{
	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
3797 3798 3799
static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
3800
	unregister_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812
	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);
3813
	register_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
3814 3815 3816 3817 3818 3819 3820 3821 3822
	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);