af_packet.c 90.5 KB
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/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		PACKET - implements raw packet sockets.
 *
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 * Authors:	Ross Biro
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 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *		Alan Cox, <gw4pts@gw4pts.ampr.org>
 *
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 * Fixes:
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 *		Alan Cox	:	verify_area() now used correctly
 *		Alan Cox	:	new skbuff lists, look ma no backlogs!
 *		Alan Cox	:	tidied skbuff lists.
 *		Alan Cox	:	Now uses generic datagram routines I
 *					added. Also fixed the peek/read crash
 *					from all old Linux datagram code.
 *		Alan Cox	:	Uses the improved datagram code.
 *		Alan Cox	:	Added NULL's for socket options.
 *		Alan Cox	:	Re-commented the code.
 *		Alan Cox	:	Use new kernel side addressing
 *		Rob Janssen	:	Correct MTU usage.
 *		Dave Platt	:	Counter leaks caused by incorrect
 *					interrupt locking and some slightly
 *					dubious gcc output. Can you read
 *					compiler: it said _VOLATILE_
 *	Richard Kooijman	:	Timestamp fixes.
 *		Alan Cox	:	New buffers. Use sk->mac.raw.
 *		Alan Cox	:	sendmsg/recvmsg support.
 *		Alan Cox	:	Protocol setting support
 *	Alexey Kuznetsov	:	Untied from IPv4 stack.
 *	Cyrus Durgin		:	Fixed kerneld for kmod.
 *	Michal Ostrowski        :       Module initialization cleanup.
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 *         Ulises Alonso        :       Frame number limit removal and
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 *                                      packet_set_ring memory leak.
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 *		Eric Biederman	:	Allow for > 8 byte hardware addresses.
 *					The convention is that longer addresses
 *					will simply extend the hardware address
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 *					byte arrays at the end of sockaddr_ll
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 *					and packet_mreq.
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 *		Johann Baudy	:	Added TX RING.
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 *		Chetan Loke	:	Implemented TPACKET_V3 block abstraction
 *					layer.
 *					Copyright (C) 2011, <lokec@ccs.neu.edu>
 *
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 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */
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#include <linux/types.h>
#include <linux/mm.h>
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#include <linux/capability.h>
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#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
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#include <linux/kernel.h>
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#include <linux/kmod.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <net/net_namespace.h>
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#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/page.h>
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#include <asm/cacheflush.h>
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#include <asm/io.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
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#include <linux/mutex.h>
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#include <linux/if_vlan.h>
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#include <linux/virtio_net.h>
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#include <linux/errqueue.h>
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#include <linux/net_tstamp.h>
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#include <linux/reciprocal_div.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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union tpacket_uhdr {
	struct tpacket_hdr  *h1;
	struct tpacket2_hdr *h2;
	struct tpacket3_hdr *h3;
	void *raw;
};

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

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#define V3_ALIGNMENT	(8)

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

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

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

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

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

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

	if (shhwtstamps) {
		if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
		    ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
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			return TP_STATUS_TS_SYS_HARDWARE;
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		if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
		    ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
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			return TP_STATUS_TS_RAW_HARDWARE;
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	}

	if (ktime_to_timespec_cond(skb->tstamp, ts))
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		return TP_STATUS_TS_SOFTWARE;
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	return 0;
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}

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

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

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

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

	return h.raw;
}

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

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

static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
		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;
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	po->stats.stats3.tp_freeze_q_cnt = 0;
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	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;
581
	struct tpacket_kbdq_core *pkc = &po->rx_ring.prb_bdqc;
582
	unsigned int frozen;
583
	struct tpacket_block_desc *pbd;
584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646

	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);
}

647
static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
648
		struct tpacket_block_desc *pbd1, __u32 status)
649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
{
	/* 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.
 */
690 691
static void prb_close_block(struct tpacket_kbdq_core *pkc1,
		struct tpacket_block_desc *pbd1,
692 693 694 695 696
		struct packet_sock *po, unsigned int stat)
{
	__u32 status = TP_STATUS_USER | stat;

	struct tpacket3_hdr *last_pkt;
697
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
698

699
	if (po->stats.stats3.tp_drops)
700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724
		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);
}

725
static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
726 727 728 729 730 731 732 733 734 735 736
{
	pkc->reset_pending_on_curr_blk = 0;
}

/*
 * Side effect of opening a block:
 *
 * 1) prb_queue is thawed.
 * 2) retire_blk_timer is refreshed.
 *
 */
737 738
static void prb_open_block(struct tpacket_kbdq_core *pkc1,
	struct tpacket_block_desc *pbd1)
739 740
{
	struct timespec ts;
741
	struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
742 743 744

	smp_rmb();

745 746 747
	/* We could have just memset this but we will lose the
	 * flexibility of making the priv area sticky
	 */
748

749 750 751
	BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
	BLOCK_NUM_PKTS(pbd1) = 0;
	BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
752

753 754 755 756
	getnstimeofday(&ts);

	h1->ts_first_pkt.ts_sec = ts.tv_sec;
	h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
757

758 759 760 761 762 763 764 765 766 767 768 769 770 771
	pkc1->pkblk_start = (char *)pbd1;
	pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);

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

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

	prb_thaw_queue(pkc1);
	_prb_refresh_rx_retire_blk_timer(pkc1);

	smp_wmb();
772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796
}

/*
 * 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.
 */
797
static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
798 799 800
				  struct packet_sock *po)
{
	pkc->reset_pending_on_curr_blk = 1;
801
	po->stats.stats3.tp_freeze_q_cnt++;
802 803 804 805 806 807 808 809 810 811
}

#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.
 */
812
static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
813 814
		struct packet_sock *po)
{
815
	struct tpacket_block_desc *pbd;
816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836

	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;
}

837
static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
838 839
		struct packet_sock *po, unsigned int status)
{
840
	struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863

	/* 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;
	}
}

864
static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
865
				      struct tpacket_block_desc *pbd)
866 867 868 869
{
	return TP_STATUS_USER & BLOCK_STATUS(pbd);
}

870
static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
871 872 873 874
{
	return pkc->reset_pending_on_curr_blk;
}

875
static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
876
{
877
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
878 879 880
	atomic_dec(&pkc->blk_fill_in_prog);
}

881
static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
882 883 884 885 886
			struct tpacket3_hdr *ppd)
{
	ppd->hv1.tp_rxhash = skb_get_rxhash(pkc->skb);
}

887
static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
888 889 890 891 892
			struct tpacket3_hdr *ppd)
{
	ppd->hv1.tp_rxhash = 0;
}

893
static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
894 895 896 897 898 899
			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 {
900 901
		ppd->hv1.tp_vlan_tci = 0;
		ppd->tp_status = TP_STATUS_AVAILABLE;
902 903 904
	}
}

905
static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
906 907 908 909 910 911 912 913 914 915
			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);
}

916
static void prb_fill_curr_block(char *curr,
917 918
				struct tpacket_kbdq_core *pkc,
				struct tpacket_block_desc *pbd,
919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939
				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
					    )
{
940 941
	struct tpacket_kbdq_core *pkc;
	struct tpacket_block_desc *pbd;
942 943
	char *curr, *end;

J
Joe Perches 已提交
944
	pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
	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
970
	end = (char *)pbd + pkc->kblk_size;
971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995

	/* 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;
}

996
static void *packet_current_rx_frame(struct packet_sock *po,
997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011
					    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();
1012
		return NULL;
1013 1014 1015
	}
}

1016
static void *prb_lookup_block(struct packet_sock *po,
1017
				     struct packet_ring_buffer *rb,
1018
				     unsigned int idx,
1019 1020
				     int status)
{
1021
	struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1022
	struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1023 1024 1025 1026 1027 1028

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

1029
static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1030 1031 1032 1033 1034 1035 1036 1037 1038 1039
{
	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 */
1040
static void *__prb_previous_block(struct packet_sock *po,
1041 1042 1043 1044 1045 1046 1047
					 struct packet_ring_buffer *rb,
					 int status)
{
	unsigned int previous = prb_previous_blk_num(rb);
	return prb_lookup_block(po, rb, previous, status);
}

1048
static void *packet_previous_rx_frame(struct packet_sock *po,
1049 1050 1051 1052 1053 1054 1055 1056 1057
					     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);
}

1058
static void packet_increment_rx_head(struct packet_sock *po,
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072
					    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;
	}
}

1073
static void *packet_previous_frame(struct packet_sock *po,
J
Johann Baudy 已提交
1074 1075 1076 1077 1078 1079 1080
		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);
}

1081
static void packet_increment_head(struct packet_ring_buffer *buff)
J
Johann Baudy 已提交
1082 1083 1084 1085
{
	buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
}

1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108
static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
{
	struct sock *sk = &po->sk;
	bool has_room;

	if (po->prot_hook.func != tpacket_rcv)
		return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
			<= sk->sk_rcvbuf;

	spin_lock(&sk->sk_receive_queue.lock);
	if (po->tp_version == TPACKET_V3)
		has_room = prb_lookup_block(po, &po->rx_ring,
					    po->rx_ring.prb_bdqc.kactive_blk_num,
					    TP_STATUS_KERNEL);
	else
		has_room = packet_lookup_frame(po, &po->rx_ring,
					       po->rx_ring.head,
					       TP_STATUS_KERNEL);
	spin_unlock(&sk->sk_receive_queue.lock);

	return has_room;
}

L
Linus Torvalds 已提交
1109 1110
static void packet_sock_destruct(struct sock *sk)
{
1111 1112
	skb_queue_purge(&sk->sk_error_queue);

1113 1114
	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
L
Linus Torvalds 已提交
1115 1116

	if (!sock_flag(sk, SOCK_DEAD)) {
E
Eric Dumazet 已提交
1117
		pr_err("Attempt to release alive packet socket: %p\n", sk);
L
Linus Torvalds 已提交
1118 1119 1120
		return;
	}

1121
	sk_refcnt_debug_dec(sk);
L
Linus Torvalds 已提交
1122 1123
}

D
David S. Miller 已提交
1124 1125 1126 1127 1128 1129 1130 1131 1132 1133
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;
}

1134 1135 1136
static unsigned int fanout_demux_hash(struct packet_fanout *f,
				      struct sk_buff *skb,
				      unsigned int num)
D
David S. Miller 已提交
1137
{
1138
	return reciprocal_divide(skb->rxhash, num);
D
David S. Miller 已提交
1139 1140
}

1141 1142 1143
static unsigned int fanout_demux_lb(struct packet_fanout *f,
				    struct sk_buff *skb,
				    unsigned int num)
D
David S. Miller 已提交
1144 1145 1146 1147 1148 1149 1150
{
	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;
1151 1152 1153 1154 1155 1156 1157 1158
	return cur;
}

static unsigned int fanout_demux_cpu(struct packet_fanout *f,
				     struct sk_buff *skb,
				     unsigned int num)
{
	return smp_processor_id() % num;
D
David S. Miller 已提交
1159 1160
}

1161 1162 1163 1164 1165 1166 1167
static unsigned int fanout_demux_rnd(struct packet_fanout *f,
				     struct sk_buff *skb,
				     unsigned int num)
{
	return reciprocal_divide(prandom_u32(), num);
}

1168 1169 1170 1171
static unsigned int fanout_demux_rollover(struct packet_fanout *f,
					  struct sk_buff *skb,
					  unsigned int idx, unsigned int skip,
					  unsigned int num)
1172
{
1173
	unsigned int i, j;
1174

1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191
	i = j = min_t(int, f->next[idx], num - 1);
	do {
		if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
			if (i != j)
				f->next[idx] = i;
			return i;
		}
		if (++i == num)
			i = 0;
	} while (i != j);

	return idx;
}

static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
{
	return f->flags & (flag >> 8);
1192 1193 1194 1195
}

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
1196 1197 1198 1199
{
	struct packet_fanout *f = pt->af_packet_priv;
	unsigned int num = f->num_members;
	struct packet_sock *po;
1200
	unsigned int idx;
D
David S. Miller 已提交
1201 1202 1203 1204 1205 1206 1207

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

1208 1209 1210
	switch (f->type) {
	case PACKET_FANOUT_HASH:
	default:
1211
		if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1212
			skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1213 1214 1215 1216
			if (!skb)
				return 0;
		}
		skb_get_rxhash(skb);
1217
		idx = fanout_demux_hash(f, skb, num);
1218 1219
		break;
	case PACKET_FANOUT_LB:
1220
		idx = fanout_demux_lb(f, skb, num);
1221 1222
		break;
	case PACKET_FANOUT_CPU:
1223 1224
		idx = fanout_demux_cpu(f, skb, num);
		break;
1225 1226 1227
	case PACKET_FANOUT_RND:
		idx = fanout_demux_rnd(f, skb, num);
		break;
1228 1229
	case PACKET_FANOUT_ROLLOVER:
		idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1230
		break;
D
David S. Miller 已提交
1231 1232
	}

1233 1234 1235 1236 1237 1238
	po = pkt_sk(f->arr[idx]);
	if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
	    unlikely(!packet_rcv_has_room(po, skb))) {
		idx = fanout_demux_rollover(f, skb, idx, idx, num);
		po = pkt_sk(f->arr[idx]);
	}
D
David S. Miller 已提交
1239 1240 1241 1242

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

1243 1244
DEFINE_MUTEX(fanout_mutex);
EXPORT_SYMBOL_GPL(fanout_mutex);
D
David S. Miller 已提交
1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273
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);
}

1274
static bool match_fanout_group(struct packet_type *ptype, struct sock * sk)
1275 1276 1277 1278 1279 1280 1281
{
	if (ptype->af_packet_priv == (void*)((struct packet_sock *)sk)->fanout)
		return true;

	return false;
}

1282
static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
D
David S. Miller 已提交
1283 1284 1285
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_fanout *f, *match;
1286
	u8 type = type_flags & 0xff;
1287
	u8 flags = type_flags >> 8;
D
David S. Miller 已提交
1288 1289 1290
	int err;

	switch (type) {
1291 1292 1293
	case PACKET_FANOUT_ROLLOVER:
		if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
			return -EINVAL;
D
David S. Miller 已提交
1294 1295
	case PACKET_FANOUT_HASH:
	case PACKET_FANOUT_LB:
1296
	case PACKET_FANOUT_CPU:
1297
	case PACKET_FANOUT_RND:
D
David S. Miller 已提交
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317
		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
1318
	err = -EINVAL;
1319
	if (match && match->flags != flags)
E
Eric Dumazet 已提交
1320
		goto out;
D
David S. Miller 已提交
1321
	if (!match) {
E
Eric Dumazet 已提交
1322
		err = -ENOMEM;
D
David S. Miller 已提交
1323
		match = kzalloc(sizeof(*match), GFP_KERNEL);
E
Eric Dumazet 已提交
1324 1325 1326 1327 1328
		if (!match)
			goto out;
		write_pnet(&match->net, sock_net(sk));
		match->id = id;
		match->type = type;
1329
		match->flags = flags;
E
Eric Dumazet 已提交
1330 1331 1332 1333 1334 1335 1336 1337
		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;
1338
		match->prot_hook.id_match = match_fanout_group;
E
Eric Dumazet 已提交
1339 1340
		dev_add_pack(&match->prot_hook);
		list_add(&match->list, &fanout_list);
D
David S. Miller 已提交
1341
	}
E
Eric Dumazet 已提交
1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352
	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
1353 1354
		}
	}
E
Eric Dumazet 已提交
1355
out:
D
David S. Miller 已提交
1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368
	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;

1369
	mutex_lock(&fanout_mutex);
D
David S. Miller 已提交
1370 1371 1372 1373 1374 1375 1376 1377 1378
	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
1379

1380
static const struct proto_ops packet_ops;
L
Linus Torvalds 已提交
1381

1382
static const struct proto_ops packet_ops_spkt;
L
Linus Torvalds 已提交
1383

E
Eric Dumazet 已提交
1384 1385
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
1386 1387 1388 1389 1390 1391 1392 1393 1394 1395
{
	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;
1396

L
Linus Torvalds 已提交
1397 1398 1399 1400 1401 1402 1403
	/*
	 *	Yank back the headers [hope the device set this
	 *	right or kerboom...]
	 *
	 *	Incoming packets have ll header pulled,
	 *	push it back.
	 *
1404
	 *	For outgoing ones skb->data == skb_mac_header(skb)
L
Linus Torvalds 已提交
1405 1406 1407 1408 1409 1410
	 *	so that this procedure is noop.
	 */

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

O
Octavian Purdila 已提交
1411
	if (!net_eq(dev_net(dev), sock_net(sk)))
1412 1413
		goto out;

E
Eric Dumazet 已提交
1414 1415
	skb = skb_share_check(skb, GFP_ATOMIC);
	if (skb == NULL)
L
Linus Torvalds 已提交
1416 1417 1418
		goto oom;

	/* drop any routing info */
E
Eric Dumazet 已提交
1419
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1420

1421 1422 1423
	/* drop conntrack reference */
	nf_reset(skb);

1424
	spkt = &PACKET_SKB_CB(skb)->sa.pkt;
L
Linus Torvalds 已提交
1425

1426
	skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440

	/*
	 *	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
1441
	if (sock_queue_rcv_skb(sk, skb) == 0)
L
Linus Torvalds 已提交
1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454
		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
 */
1455

L
Linus Torvalds 已提交
1456 1457 1458 1459
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
1460
	struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
1461
	struct sk_buff *skb = NULL;
L
Linus Torvalds 已提交
1462
	struct net_device *dev;
E
Eric Dumazet 已提交
1463
	__be16 proto = 0;
L
Linus Torvalds 已提交
1464
	int err;
1465
	int extra_len = 0;
1466

L
Linus Torvalds 已提交
1467
	/*
1468
	 *	Get and verify the address.
L
Linus Torvalds 已提交
1469 1470
	 */

E
Eric Dumazet 已提交
1471
	if (saddr) {
L
Linus Torvalds 已提交
1472
		if (msg->msg_namelen < sizeof(struct sockaddr))
E
Eric Dumazet 已提交
1473 1474 1475 1476 1477
			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
1478 1479

	/*
1480
	 *	Find the device first to size check it
L
Linus Torvalds 已提交
1481 1482
	 */

1483
	saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1484
retry:
E
Eric Dumazet 已提交
1485 1486
	rcu_read_lock();
	dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
L
Linus Torvalds 已提交
1487 1488 1489
	err = -ENODEV;
	if (dev == NULL)
		goto out_unlock;
1490

1491 1492 1493 1494
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

L
Linus Torvalds 已提交
1495
	/*
E
Eric Dumazet 已提交
1496 1497
	 * 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
1498
	 */
1499

1500 1501 1502 1503 1504 1505 1506 1507
	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
1508
	err = -EMSGSIZE;
1509
	if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
L
Linus Torvalds 已提交
1510 1511
		goto out_unlock;

1512 1513
	if (!skb) {
		size_t reserved = LL_RESERVED_SPACE(dev);
1514
		int tlen = dev->needed_tailroom;
1515 1516 1517
		unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;

		rcu_read_unlock();
1518
		skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538
		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
1539 1540
	}

1541
	if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553
		/* 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;
		}
	}
1554

L
Linus Torvalds 已提交
1555 1556 1557
	skb->protocol = proto;
	skb->dev = dev;
	skb->priority = sk->sk_priority;
1558
	skb->mark = sk->sk_mark;
1559 1560

	sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
L
Linus Torvalds 已提交
1561

1562 1563 1564
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

1565
	skb_probe_transport_header(skb, 0);
1566

L
Linus Torvalds 已提交
1567
	dev_queue_xmit(skb);
E
Eric Dumazet 已提交
1568
	rcu_read_unlock();
E
Eric Dumazet 已提交
1569
	return len;
L
Linus Torvalds 已提交
1570 1571

out_unlock:
E
Eric Dumazet 已提交
1572
	rcu_read_unlock();
1573 1574
out_free:
	kfree_skb(skb);
L
Linus Torvalds 已提交
1575 1576 1577
	return err;
}

1578
static unsigned int run_filter(const struct sk_buff *skb,
E
Eric Dumazet 已提交
1579
				      const struct sock *sk,
D
David S. Miller 已提交
1580
				      unsigned int res)
L
Linus Torvalds 已提交
1581 1582
{
	struct sk_filter *filter;
1583

1584 1585
	rcu_read_lock();
	filter = rcu_dereference(sk->sk_filter);
D
David S. Miller 已提交
1586
	if (filter != NULL)
1587
		res = SK_RUN_FILTER(filter, skb);
1588
	rcu_read_unlock();
L
Linus Torvalds 已提交
1589

D
David S. Miller 已提交
1590
	return res;
L
Linus Torvalds 已提交
1591 1592 1593
}

/*
E
Eric Dumazet 已提交
1594 1595 1596 1597 1598 1599 1600 1601 1602
 * 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
1603 1604
 */

E
Eric Dumazet 已提交
1605 1606
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
1607 1608 1609 1610
{
	struct sock *sk;
	struct sockaddr_ll *sll;
	struct packet_sock *po;
E
Eric Dumazet 已提交
1611
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
1612
	int skb_len = skb->len;
D
David S. Miller 已提交
1613
	unsigned int snaplen, res;
L
Linus Torvalds 已提交
1614 1615 1616 1617 1618 1619 1620

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

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

O
Octavian Purdila 已提交
1621
	if (!net_eq(dev_net(dev), sock_net(sk)))
1622 1623
		goto drop;

L
Linus Torvalds 已提交
1624 1625
	skb->dev = dev;

1626
	if (dev->header_ops) {
L
Linus Torvalds 已提交
1627
		/* The device has an explicit notion of ll header,
E
Eric Dumazet 已提交
1628 1629 1630 1631 1632
		 * 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
1633 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
		}
	}

	snaplen = skb->len;

D
David S. Miller 已提交
1644 1645
	res = run_filter(skb, sk, snaplen);
	if (!res)
1646
		goto drop_n_restore;
D
David S. Miller 已提交
1647 1648
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
1649

E
Eric Dumazet 已提交
1650
	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
L
Linus Torvalds 已提交
1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661
		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;
		}
1662
		consume_skb(skb);
L
Linus Torvalds 已提交
1663 1664 1665
		skb = nskb;
	}

1666 1667 1668 1669
	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
1670 1671 1672 1673
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
1674
	if (unlikely(po->origdev))
1675 1676 1677
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
1678

S
Stephen Hemminger 已提交
1679
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
1680

1681
	PACKET_SKB_CB(skb)->origlen = skb->len;
1682

L
Linus Torvalds 已提交
1683 1684 1685 1686 1687
	if (pskb_trim(skb, snaplen))
		goto drop_n_acct;

	skb_set_owner_r(skb, sk);
	skb->dev = NULL;
E
Eric Dumazet 已提交
1688
	skb_dst_drop(skb);
L
Linus Torvalds 已提交
1689

1690 1691 1692
	/* drop conntrack reference */
	nf_reset(skb);

L
Linus Torvalds 已提交
1693
	spin_lock(&sk->sk_receive_queue.lock);
1694
	po->stats.stats1.tp_packets++;
1695
	skb->dropcount = atomic_read(&sk->sk_drops);
L
Linus Torvalds 已提交
1696 1697 1698 1699 1700 1701
	__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:
1702
	spin_lock(&sk->sk_receive_queue.lock);
1703
	po->stats.stats1.tp_drops++;
1704 1705
	atomic_inc(&sk->sk_drops);
	spin_unlock(&sk->sk_receive_queue.lock);
L
Linus Torvalds 已提交
1706 1707 1708 1709 1710 1711 1712

drop_n_restore:
	if (skb_head != skb->data && skb_shared(skb)) {
		skb->data = skb_head;
		skb->len = skb_len;
	}
drop:
1713
	consume_skb(skb);
L
Linus Torvalds 已提交
1714 1715 1716
	return 0;
}

E
Eric Dumazet 已提交
1717 1718
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
1719 1720 1721 1722
{
	struct sock *sk;
	struct packet_sock *po;
	struct sockaddr_ll *sll;
1723
	union tpacket_uhdr h;
E
Eric Dumazet 已提交
1724
	u8 *skb_head = skb->data;
L
Linus Torvalds 已提交
1725
	int skb_len = skb->len;
D
David S. Miller 已提交
1726
	unsigned int snaplen, res;
1727
	unsigned long status = TP_STATUS_USER;
1728
	unsigned short macoff, netoff, hdrlen;
L
Linus Torvalds 已提交
1729
	struct sk_buff *copy_skb = NULL;
1730
	struct timespec ts;
1731
	__u32 ts_status;
L
Linus Torvalds 已提交
1732 1733 1734 1735 1736 1737 1738

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

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

O
Octavian Purdila 已提交
1739
	if (!net_eq(dev_net(dev), sock_net(sk)))
1740 1741
		goto drop;

1742
	if (dev->header_ops) {
L
Linus Torvalds 已提交
1743
		if (sk->sk_type != SOCK_DGRAM)
1744
			skb_push(skb, skb->data - skb_mac_header(skb));
L
Linus Torvalds 已提交
1745 1746
		else if (skb->pkt_type == PACKET_OUTGOING) {
			/* Special case: outgoing packets have ll header at head */
1747
			skb_pull(skb, skb_network_offset(skb));
L
Linus Torvalds 已提交
1748 1749 1750
		}
	}

1751 1752 1753
	if (skb->ip_summed == CHECKSUM_PARTIAL)
		status |= TP_STATUS_CSUMNOTREADY;

L
Linus Torvalds 已提交
1754 1755
	snaplen = skb->len;

D
David S. Miller 已提交
1756 1757
	res = run_filter(skb, sk, snaplen);
	if (!res)
1758
		goto drop_n_restore;
D
David S. Miller 已提交
1759 1760
	if (snaplen > res)
		snaplen = res;
L
Linus Torvalds 已提交
1761 1762

	if (sk->sk_type == SOCK_DGRAM) {
1763 1764
		macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
				  po->tp_reserve;
L
Linus Torvalds 已提交
1765
	} else {
1766
		unsigned int maclen = skb_network_offset(skb);
1767
		netoff = TPACKET_ALIGN(po->tp_hdrlen +
1768 1769
				       (maclen < 16 ? 16 : maclen)) +
			po->tp_reserve;
L
Linus Torvalds 已提交
1770 1771
		macoff = netoff - maclen;
	}
1772 1773 1774
	if (po->tp_version <= TPACKET_V2) {
		if (macoff + snaplen > po->rx_ring.frame_size) {
			if (po->copy_thresh &&
E
Eric Dumazet 已提交
1775
			    atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1776 1777 1778 1779 1780 1781 1782 1783
				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
1784
			}
1785 1786 1787
			snaplen = po->rx_ring.frame_size - macoff;
			if ((int)snaplen < 0)
				snaplen = 0;
L
Linus Torvalds 已提交
1788 1789 1790
		}
	}
	spin_lock(&sk->sk_receive_queue.lock);
1791 1792
	h.raw = packet_current_rx_frame(po, skb,
					TP_STATUS_KERNEL, (macoff+snaplen));
1793
	if (!h.raw)
L
Linus Torvalds 已提交
1794
		goto ring_is_full;
1795 1796 1797 1798 1799 1800 1801 1802
	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.
	 */
1803
		if (po->stats.stats1.tp_drops)
1804 1805
			status |= TP_STATUS_LOSING;
	}
1806
	po->stats.stats1.tp_packets++;
L
Linus Torvalds 已提交
1807 1808 1809 1810 1811 1812
	if (copy_skb) {
		status |= TP_STATUS_COPY;
		__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
	}
	spin_unlock(&sk->sk_receive_queue.lock);

1813
	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1814 1815

	if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1816
		getnstimeofday(&ts);
L
Linus Torvalds 已提交
1817

1818 1819
	status |= ts_status;

1820 1821 1822 1823 1824 1825
	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;
1826 1827
		h.h1->tp_sec = ts.tv_sec;
		h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
1828 1829 1830 1831 1832 1833 1834 1835 1836
		hdrlen = sizeof(*h.h1);
		break;
	case TPACKET_V2:
		h.h2->tp_len = skb->len;
		h.h2->tp_snaplen = snaplen;
		h.h2->tp_mac = macoff;
		h.h2->tp_net = netoff;
		h.h2->tp_sec = ts.tv_sec;
		h.h2->tp_nsec = ts.tv_nsec;
1837 1838 1839 1840 1841 1842
		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;
		}
1843
		h.h2->tp_padding = 0;
1844 1845
		hdrlen = sizeof(*h.h2);
		break;
1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
	case TPACKET_V3:
		/* tp_nxt_offset,vlan are already populated above.
		 * So DONT clear those fields here
		 */
		h.h3->tp_status |= status;
		h.h3->tp_len = skb->len;
		h.h3->tp_snaplen = snaplen;
		h.h3->tp_mac = macoff;
		h.h3->tp_net = netoff;
		h.h3->tp_sec  = ts.tv_sec;
		h.h3->tp_nsec = ts.tv_nsec;
		hdrlen = sizeof(*h.h3);
		break;
1859 1860 1861
	default:
		BUG();
	}
L
Linus Torvalds 已提交
1862

1863
	sll = h.raw + TPACKET_ALIGN(hdrlen);
S
Stephen Hemminger 已提交
1864
	sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
L
Linus Torvalds 已提交
1865 1866 1867 1868
	sll->sll_family = AF_PACKET;
	sll->sll_hatype = dev->type;
	sll->sll_protocol = skb->protocol;
	sll->sll_pkttype = skb->pkt_type;
1869
	if (unlikely(po->origdev))
1870 1871 1872
		sll->sll_ifindex = orig_dev->ifindex;
	else
		sll->sll_ifindex = dev->ifindex;
L
Linus Torvalds 已提交
1873

R
Ralf Baechle 已提交
1874
	smp_mb();
1875
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
L
Linus Torvalds 已提交
1876
	{
1877 1878
		u8 *start, *end;

1879 1880 1881 1882 1883 1884
		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));
		}
1885
		smp_wmb();
L
Linus Torvalds 已提交
1886
	}
1887
#endif
1888 1889 1890 1891
	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
1892 1893 1894 1895 1896 1897 1898 1899 1900

	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:
1901
	kfree_skb(skb);
L
Linus Torvalds 已提交
1902 1903 1904
	return 0;

ring_is_full:
1905
	po->stats.stats1.tp_drops++;
L
Linus Torvalds 已提交
1906 1907 1908
	spin_unlock(&sk->sk_receive_queue.lock);

	sk->sk_data_ready(sk, 0);
1909
	kfree_skb(copy_skb);
L
Linus Torvalds 已提交
1910 1911 1912
	goto drop_n_restore;
}

J
Johann Baudy 已提交
1913 1914 1915
static void tpacket_destruct_skb(struct sk_buff *skb)
{
	struct packet_sock *po = pkt_sk(skb->sk);
E
Eric Dumazet 已提交
1916
	void *ph;
L
Linus Torvalds 已提交
1917

J
Johann Baudy 已提交
1918
	if (likely(po->tx_ring.pg_vec)) {
1919 1920
		__u32 ts;

J
Johann Baudy 已提交
1921 1922 1923
		ph = skb_shinfo(skb)->destructor_arg;
		BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
		atomic_dec(&po->tx_ring.pending);
1924 1925 1926

		ts = __packet_set_timestamp(po, ph, skb);
		__packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
J
Johann Baudy 已提交
1927 1928 1929 1930 1931
	}

	sock_wfree(skb);
}

E
Eric Dumazet 已提交
1932 1933
static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
		void *frame, struct net_device *dev, int size_max,
1934
		__be16 proto, unsigned char *addr, int hlen)
J
Johann Baudy 已提交
1935
{
1936
	union tpacket_uhdr ph;
1937
	int to_write, offset, len, tp_len, nr_frags, len_max;
J
Johann Baudy 已提交
1938 1939 1940 1941 1942 1943 1944 1945 1946 1947
	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;
1948
	skb->mark = po->sk.sk_mark;
1949
	sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
J
Johann Baudy 已提交
1950 1951 1952 1953 1954 1955 1956 1957 1958 1959
	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;
	}
1960 1961 1962 1963
	if (unlikely(tp_len > size_max)) {
		pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
		return -EMSGSIZE;
	}
J
Johann Baudy 已提交
1964

1965
	skb_reserve(skb, hlen);
J
Johann Baudy 已提交
1966
	skb_reset_network_header(skb);
1967
	skb_probe_transport_header(skb, 0);
1968

1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
	if (po->tp_tx_has_off) {
		int off_min, off_max, off;
		off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
		off_max = po->tx_ring.frame_size - tp_len;
		if (sock->type == SOCK_DGRAM) {
			switch (po->tp_version) {
			case TPACKET_V2:
				off = ph.h2->tp_net;
				break;
			default:
				off = ph.h1->tp_net;
				break;
			}
		} else {
			switch (po->tp_version) {
			case TPACKET_V2:
				off = ph.h2->tp_mac;
				break;
			default:
				off = ph.h1->tp_mac;
				break;
			}
		}
		if (unlikely((off < off_min) || (off_max < off)))
			return -EINVAL;
		data = ph.raw + off;
	} else {
		data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
	}
J
Johann Baudy 已提交
1998 1999 2000 2001 2002 2003 2004
	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
2005
	} else if (dev->hard_header_len) {
J
Johann Baudy 已提交
2006 2007
		/* net device doesn't like empty head */
		if (unlikely(tp_len <= dev->hard_header_len)) {
E
Eric Dumazet 已提交
2008 2009
			pr_err("packet size is too short (%d < %d)\n",
			       tp_len, dev->hard_header_len);
J
Johann Baudy 已提交
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035
			return -EINVAL;
		}

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

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

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

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

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

		if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
E
Eric Dumazet 已提交
2036 2037
			pr_err("Packet exceed the number of skb frags(%lu)\n",
			       MAX_SKB_FRAGS);
J
Johann Baudy 已提交
2038 2039 2040
			return -EFAULT;
		}

2041 2042
		page = pgv_to_page(data);
		data += len;
J
Johann Baudy 已提交
2043 2044
		flush_dcache_page(page);
		get_page(page);
2045
		skb_fill_page_desc(skb, nr_frags, page, offset, len);
J
Johann Baudy 已提交
2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059
		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;
2060
	bool need_rls_dev = false;
2061
	int err, reserve = 0;
E
Eric Dumazet 已提交
2062 2063
	void *ph;
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
J
Johann Baudy 已提交
2064 2065 2066
	int tp_len, size_max;
	unsigned char *addr;
	int len_sum = 0;
2067
	int status = TP_STATUS_AVAILABLE;
2068
	int hlen, tlen;
J
Johann Baudy 已提交
2069 2070 2071 2072

	mutex_lock(&po->pg_vec_lock);

	if (saddr == NULL) {
2073
		dev = po->prot_hook.dev;
J
Johann Baudy 已提交
2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085
		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;
2086 2087
		dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
		need_rls_dev = true;
J
Johann Baudy 已提交
2088 2089 2090 2091 2092 2093
	}

	err = -ENXIO;
	if (unlikely(dev == NULL))
		goto out;

2094 2095
	reserve = dev->hard_header_len;

J
Johann Baudy 已提交
2096 2097 2098 2099 2100
	err = -ENETDOWN;
	if (unlikely(!(dev->flags & IFF_UP)))
		goto out_put;

	size_max = po->tx_ring.frame_size
2101
		- (po->tp_hdrlen - sizeof(struct sockaddr_ll));
J
Johann Baudy 已提交
2102

2103 2104 2105
	if (size_max > dev->mtu + reserve)
		size_max = dev->mtu + reserve;

J
Johann Baudy 已提交
2106 2107 2108 2109 2110 2111 2112 2113 2114 2115
	do {
		ph = packet_current_frame(po, &po->tx_ring,
				TP_STATUS_SEND_REQUEST);

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

		status = TP_STATUS_SEND_REQUEST;
2116 2117
		hlen = LL_RESERVED_SPACE(dev);
		tlen = dev->needed_tailroom;
J
Johann Baudy 已提交
2118
		skb = sock_alloc_send_skb(&po->sk,
2119
				hlen + tlen + sizeof(struct sockaddr_ll),
J
Johann Baudy 已提交
2120 2121 2122 2123 2124 2125
				0, &err);

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

		tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2126
				addr, hlen);
J
Johann Baudy 已提交
2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147

		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);
2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161
		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
2162 2163
		packet_increment_head(&po->tx_ring);
		len_sum += tp_len;
2164 2165 2166 2167
	} while (likely((ph != NULL) ||
			((!(msg->msg_flags & MSG_DONTWAIT)) &&
			 (atomic_read(&po->tx_ring.pending))))
		);
J
Johann Baudy 已提交
2168 2169 2170 2171 2172 2173 2174 2175

	err = len_sum;
	goto out_put;

out_status:
	__packet_set_status(po, ph, status);
	kfree_skb(skb);
out_put:
2176 2177
	if (need_rls_dev)
		dev_put(dev);
J
Johann Baudy 已提交
2178 2179 2180 2181 2182
out:
	mutex_unlock(&po->pg_vec_lock);
	return err;
}

2183 2184 2185 2186
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)
2187 2188 2189 2190 2191 2192 2193 2194
{
	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,
2195
				   err, 0);
2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206
	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
2207
static int packet_snd(struct socket *sock,
L
Linus Torvalds 已提交
2208 2209 2210
			  struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
E
Eric Dumazet 已提交
2211
	struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
L
Linus Torvalds 已提交
2212 2213
	struct sk_buff *skb;
	struct net_device *dev;
A
Al Viro 已提交
2214
	__be16 proto;
2215
	bool need_rls_dev = false;
L
Linus Torvalds 已提交
2216
	unsigned char *addr;
2217
	int err, reserve = 0;
2218 2219 2220 2221 2222
	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;
2223
	int hlen, tlen;
2224
	int extra_len = 0;
L
Linus Torvalds 已提交
2225 2226

	/*
2227
	 *	Get and verify the address.
L
Linus Torvalds 已提交
2228
	 */
2229

L
Linus Torvalds 已提交
2230
	if (saddr == NULL) {
2231
		dev = po->prot_hook.dev;
L
Linus Torvalds 已提交
2232 2233 2234 2235 2236 2237
		proto	= po->num;
		addr	= NULL;
	} else {
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(struct sockaddr_ll))
			goto out;
2238 2239
		if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
			goto out;
L
Linus Torvalds 已提交
2240 2241
		proto	= saddr->sll_protocol;
		addr	= saddr->sll_addr;
2242 2243
		dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
		need_rls_dev = true;
L
Linus Torvalds 已提交
2244 2245 2246 2247 2248 2249 2250 2251
	}

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

2252 2253 2254 2255
	err = -ENETDOWN;
	if (!(dev->flags & IFF_UP))
		goto out_unlock;

2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303
	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;

		}
	}

2304 2305 2306 2307 2308 2309 2310 2311
	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
2312
	err = -EMSGSIZE;
2313
	if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
L
Linus Torvalds 已提交
2314 2315
		goto out_unlock;

2316
	err = -ENOBUFS;
2317 2318 2319
	hlen = LL_RESERVED_SPACE(dev);
	tlen = dev->needed_tailroom;
	skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2320
			       msg->msg_flags & MSG_DONTWAIT, &err);
E
Eric Dumazet 已提交
2321
	if (skb == NULL)
L
Linus Torvalds 已提交
2322 2323
		goto out_unlock;

2324
	skb_set_network_header(skb, reserve);
L
Linus Torvalds 已提交
2325

2326 2327
	err = -EINVAL;
	if (sock->type == SOCK_DGRAM &&
2328
	    (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2329
		goto out_free;
L
Linus Torvalds 已提交
2330 2331

	/* Returns -EFAULT on error */
2332
	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
L
Linus Torvalds 已提交
2333 2334
	if (err)
		goto out_free;
2335 2336

	sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
L
Linus Torvalds 已提交
2337

2338
	if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349
		/* 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;
		}
2350 2351
	}

2352 2353
	skb->protocol = proto;
	skb->dev = dev;
L
Linus Torvalds 已提交
2354
	skb->priority = sk->sk_priority;
2355
	skb->mark = sk->sk_mark;
L
Linus Torvalds 已提交
2356

2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375
	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;
	}

2376
	skb_probe_transport_header(skb, reserve);
2377

2378 2379 2380
	if (unlikely(extra_len == 4))
		skb->no_fcs = 1;

L
Linus Torvalds 已提交
2381 2382 2383 2384 2385 2386 2387 2388
	/*
	 *	Now send it
	 */

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

2389 2390
	if (need_rls_dev)
		dev_put(dev);
L
Linus Torvalds 已提交
2391

E
Eric Dumazet 已提交
2392
	return len;
L
Linus Torvalds 已提交
2393 2394 2395 2396

out_free:
	kfree_skb(skb);
out_unlock:
2397
	if (dev && need_rls_dev)
L
Linus Torvalds 已提交
2398 2399 2400 2401 2402
		dev_put(dev);
out:
	return err;
}

J
Johann Baudy 已提交
2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413
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
2414 2415 2416 2417 2418 2419 2420 2421 2422
/*
 *	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;
2423
	struct net *net;
2424
	union tpacket_req_u req_u;
L
Linus Torvalds 已提交
2425 2426 2427 2428

	if (!sk)
		return 0;

2429
	net = sock_net(sk);
L
Linus Torvalds 已提交
2430 2431
	po = pkt_sk(sk);

2432
	mutex_lock(&net->packet.sklist_lock);
2433
	sk_del_node_init_rcu(sk);
2434 2435 2436
	mutex_unlock(&net->packet.sklist_lock);

	preempt_disable();
2437
	sock_prot_inuse_add(net, sk->sk_prot, -1);
2438
	preempt_enable();
L
Linus Torvalds 已提交
2439

2440
	spin_lock(&po->bind_lock);
2441
	unregister_prot_hook(sk, false);
2442 2443 2444 2445
	if (po->prot_hook.dev) {
		dev_put(po->prot_hook.dev);
		po->prot_hook.dev = NULL;
	}
2446
	spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
2447 2448 2449

	packet_flush_mclist(sk);

2450 2451
	if (po->rx_ring.pg_vec) {
		memset(&req_u, 0, sizeof(req_u));
2452
		packet_set_ring(sk, &req_u, 1, 0);
2453
	}
J
Johann Baudy 已提交
2454

2455 2456
	if (po->tx_ring.pg_vec) {
		memset(&req_u, 0, sizeof(req_u));
2457
		packet_set_ring(sk, &req_u, 1, 1);
2458
	}
L
Linus Torvalds 已提交
2459

D
David S. Miller 已提交
2460 2461
	fanout_release(sk);

2462
	synchronize_net();
L
Linus Torvalds 已提交
2463 2464 2465 2466 2467 2468 2469 2470 2471
	/*
	 *	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);
2472
	sk_refcnt_debug_release(sk);
L
Linus Torvalds 已提交
2473 2474 2475 2476 2477 2478 2479 2480 2481

	sock_put(sk);
	return 0;
}

/*
 *	Attach a packet hook.
 */

A
Al Viro 已提交
2482
static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
L
Linus Torvalds 已提交
2483 2484
{
	struct packet_sock *po = pkt_sk(sk);
D
David S. Miller 已提交
2485

2486 2487 2488 2489
	if (po->fanout) {
		if (dev)
			dev_put(dev);

D
David S. Miller 已提交
2490
		return -EINVAL;
2491
	}
L
Linus Torvalds 已提交
2492 2493 2494 2495

	lock_sock(sk);

	spin_lock(&po->bind_lock);
2496
	unregister_prot_hook(sk, true);
L
Linus Torvalds 已提交
2497 2498
	po->num = protocol;
	po->prot_hook.type = protocol;
2499 2500
	if (po->prot_hook.dev)
		dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
2501 2502 2503 2504 2505 2506 2507
	po->prot_hook.dev = dev;

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

	if (protocol == 0)
		goto out_unlock;

2508
	if (!dev || (dev->flags & IFF_UP)) {
2509
		register_prot_hook(sk);
2510 2511 2512 2513
	} else {
		sk->sk_err = ENETDOWN;
		if (!sock_flag(sk, SOCK_DEAD))
			sk->sk_error_report(sk);
L
Linus Torvalds 已提交
2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525
	}

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
2526 2527
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
			    int addr_len)
L
Linus Torvalds 已提交
2528
{
E
Eric Dumazet 已提交
2529
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2530 2531 2532
	char name[15];
	struct net_device *dev;
	int err = -ENODEV;
2533

L
Linus Torvalds 已提交
2534 2535 2536
	/*
	 *	Check legality
	 */
2537

2538
	if (addr_len != sizeof(struct sockaddr))
L
Linus Torvalds 已提交
2539
		return -EINVAL;
E
Eric Dumazet 已提交
2540
	strlcpy(name, uaddr->sa_data, sizeof(name));
L
Linus Torvalds 已提交
2541

2542
	dev = dev_get_by_name(sock_net(sk), name);
2543
	if (dev)
L
Linus Torvalds 已提交
2544 2545 2546 2547 2548 2549
		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
2550 2551
	struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
2552 2553 2554 2555 2556 2557 2558
	struct net_device *dev = NULL;
	int err;


	/*
	 *	Check legality
	 */
2559

L
Linus Torvalds 已提交
2560 2561 2562 2563 2564 2565 2566
	if (addr_len < sizeof(struct sockaddr_ll))
		return -EINVAL;
	if (sll->sll_family != AF_PACKET)
		return -EINVAL;

	if (sll->sll_ifindex) {
		err = -ENODEV;
2567
		dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
L
Linus Torvalds 已提交
2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583
		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),
};

/*
2584
 *	Create a packet of type SOCK_PACKET.
L
Linus Torvalds 已提交
2585 2586
 */

2587 2588
static int packet_create(struct net *net, struct socket *sock, int protocol,
			 int kern)
L
Linus Torvalds 已提交
2589 2590 2591
{
	struct sock *sk;
	struct packet_sock *po;
A
Al Viro 已提交
2592
	__be16 proto = (__force __be16)protocol; /* weird, but documented */
L
Linus Torvalds 已提交
2593 2594
	int err;

2595
	if (!ns_capable(net->user_ns, CAP_NET_RAW))
L
Linus Torvalds 已提交
2596
		return -EPERM;
2597 2598
	if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
	    sock->type != SOCK_PACKET)
L
Linus Torvalds 已提交
2599 2600 2601 2602 2603
		return -ESOCKTNOSUPPORT;

	sock->state = SS_UNCONNECTED;

	err = -ENOBUFS;
2604
	sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
L
Linus Torvalds 已提交
2605 2606 2607 2608 2609 2610
	if (sk == NULL)
		goto out;

	sock->ops = &packet_ops;
	if (sock->type == SOCK_PACKET)
		sock->ops = &packet_ops_spkt;
2611

L
Linus Torvalds 已提交
2612 2613 2614 2615
	sock_init_data(sock, sk);

	po = pkt_sk(sk);
	sk->sk_family = PF_PACKET;
A
Al Viro 已提交
2616
	po->num = proto;
L
Linus Torvalds 已提交
2617 2618

	sk->sk_destruct = packet_sock_destruct;
2619
	sk_refcnt_debug_inc(sk);
L
Linus Torvalds 已提交
2620 2621 2622 2623 2624 2625

	/*
	 *	Attach a protocol block
	 */

	spin_lock_init(&po->bind_lock);
2626
	mutex_init(&po->pg_vec_lock);
L
Linus Torvalds 已提交
2627
	po->prot_hook.func = packet_rcv;
2628

L
Linus Torvalds 已提交
2629 2630
	if (sock->type == SOCK_PACKET)
		po->prot_hook.func = packet_rcv_spkt;
2631

L
Linus Torvalds 已提交
2632 2633
	po->prot_hook.af_packet_priv = sk;

A
Al Viro 已提交
2634 2635
	if (proto) {
		po->prot_hook.type = proto;
2636
		register_prot_hook(sk);
L
Linus Torvalds 已提交
2637 2638
	}

2639
	mutex_lock(&net->packet.sklist_lock);
2640
	sk_add_node_rcu(sk, &net->packet.sklist);
2641 2642 2643
	mutex_unlock(&net->packet.sklist_lock);

	preempt_disable();
2644
	sock_prot_inuse_add(net, &packet_proto, 1);
2645
	preempt_enable();
2646

E
Eric Dumazet 已提交
2647
	return 0;
L
Linus Torvalds 已提交
2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662
out:
	return err;
}

/*
 *	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;
2663
	struct sockaddr_ll *sll;
2664
	int vnet_hdr_len = 0;
L
Linus Torvalds 已提交
2665 2666

	err = -EINVAL;
2667
	if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
L
Linus Torvalds 已提交
2668 2669 2670 2671 2672 2673 2674 2675
		goto out;

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

2676
	if (flags & MSG_ERRQUEUE) {
2677 2678
		err = sock_recv_errqueue(sk, msg, len,
					 SOL_PACKET, PACKET_TX_TIMESTAMP);
2679 2680 2681
		goto out;
	}

L
Linus Torvalds 已提交
2682 2683 2684 2685 2686 2687 2688 2689 2690
	/*
	 *	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
2691
	skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
L
Linus Torvalds 已提交
2692 2693

	/*
2694
	 *	An error occurred so return it. Because skb_recv_datagram()
L
Linus Torvalds 已提交
2695 2696 2697 2698
	 *	handles the blocking we don't see and worry about blocking
	 *	retries.
	 */

2699
	if (skb == NULL)
L
Linus Torvalds 已提交
2700 2701
		goto out;

2702 2703 2704 2705 2706
	if (pkt_sk(sk)->has_vnet_hdr) {
		struct virtio_net_hdr vnet_hdr = { 0 };

		err = -EINVAL;
		vnet_hdr_len = sizeof(vnet_hdr);
2707
		if (len < vnet_hdr_len)
2708 2709
			goto out_free;

2710 2711
		len -= vnet_hdr_len;

2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734
		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;
2735
			vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2736
			vnet_hdr.csum_offset = skb->csum_offset;
2737 2738
		} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
			vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2739 2740 2741 2742 2743 2744 2745 2746
		} /* else everything is zero */

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

2747 2748 2749 2750 2751
	/*
	 *	If the address length field is there to be filled in, we fill
	 *	it in now.
	 */

2752
	sll = &PACKET_SKB_CB(skb)->sa.ll;
2753 2754 2755 2756 2757
	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
2758 2759 2760 2761 2762 2763
	/*
	 *	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
2764 2765 2766
	if (copied > len) {
		copied = len;
		msg->msg_flags |= MSG_TRUNC;
L
Linus Torvalds 已提交
2767 2768 2769 2770 2771 2772
	}

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

2773
	sock_recv_ts_and_drops(msg, sk, skb);
L
Linus Torvalds 已提交
2774 2775

	if (msg->msg_name)
2776 2777
		memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
		       msg->msg_namelen);
L
Linus Torvalds 已提交
2778

2779
	if (pkt_sk(sk)->auxdata) {
2780 2781 2782 2783 2784 2785 2786 2787
		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;
2788
		aux.tp_net = skb_network_offset(skb);
2789 2790 2791 2792 2793 2794
		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;
		}
2795
		aux.tp_padding = 0;
2796
		put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2797 2798
	}

L
Linus Torvalds 已提交
2799 2800 2801 2802
	/*
	 *	Free or return the buffer as appropriate. Again this
	 *	hides all the races and re-entrancy issues from us.
	 */
2803
	err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
L
Linus Torvalds 已提交
2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820

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;
2821
	memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
E
Eric Dumazet 已提交
2822 2823 2824
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
	if (dev)
2825
		strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
E
Eric Dumazet 已提交
2826
	rcu_read_unlock();
L
Linus Torvalds 已提交
2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837
	*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);
2838
	DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
L
Linus Torvalds 已提交
2839 2840 2841 2842 2843 2844 2845

	if (peer)
		return -EOPNOTSUPP;

	sll->sll_family = AF_PACKET;
	sll->sll_ifindex = po->ifindex;
	sll->sll_protocol = po->num;
2846
	sll->sll_pkttype = 0;
E
Eric Dumazet 已提交
2847 2848
	rcu_read_lock();
	dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
L
Linus Torvalds 已提交
2849 2850 2851 2852 2853 2854 2855 2856
	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
2857
	rcu_read_unlock();
2858
	*uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
L
Linus Torvalds 已提交
2859 2860 2861 2862

	return 0;
}

2863 2864
static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
			 int what)
L
Linus Torvalds 已提交
2865 2866 2867
{
	switch (i->type) {
	case PACKET_MR_MULTICAST:
2868 2869
		if (i->alen != dev->addr_len)
			return -EINVAL;
L
Linus Torvalds 已提交
2870
		if (what > 0)
2871
			return dev_mc_add(dev, i->addr);
L
Linus Torvalds 已提交
2872
		else
2873
			return dev_mc_del(dev, i->addr);
L
Linus Torvalds 已提交
2874 2875
		break;
	case PACKET_MR_PROMISC:
2876
		return dev_set_promiscuity(dev, what);
L
Linus Torvalds 已提交
2877 2878
		break;
	case PACKET_MR_ALLMULTI:
2879
		return dev_set_allmulti(dev, what);
L
Linus Torvalds 已提交
2880
		break;
2881
	case PACKET_MR_UNICAST:
2882 2883
		if (i->alen != dev->addr_len)
			return -EINVAL;
2884
		if (what > 0)
2885
			return dev_uc_add(dev, i->addr);
2886
		else
2887
			return dev_uc_del(dev, i->addr);
2888
		break;
E
Eric Dumazet 已提交
2889 2890
	default:
		break;
L
Linus Torvalds 已提交
2891
	}
2892
	return 0;
L
Linus Torvalds 已提交
2893 2894 2895 2896
}

static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
{
E
Eric Dumazet 已提交
2897
	for ( ; i; i = i->next) {
L
Linus Torvalds 已提交
2898 2899 2900 2901 2902
		if (i->ifindex == dev->ifindex)
			packet_dev_mc(dev, i, what);
	}
}

2903
static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
2904 2905 2906 2907 2908 2909 2910 2911 2912
{
	struct packet_sock *po = pkt_sk(sk);
	struct packet_mclist *ml, *i;
	struct net_device *dev;
	int err;

	rtnl_lock();

	err = -ENODEV;
2913
	dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
L
Linus Torvalds 已提交
2914 2915 2916 2917
	if (!dev)
		goto done;

	err = -EINVAL;
2918
	if (mreq->mr_alen > dev->addr_len)
L
Linus Torvalds 已提交
2919 2920 2921
		goto done;

	err = -ENOBUFS;
2922
	i = kmalloc(sizeof(*i), GFP_KERNEL);
L
Linus Torvalds 已提交
2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945
	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;
2946 2947 2948 2949 2950
	err = packet_dev_mc(dev, i, 1);
	if (err) {
		po->mclist = i->next;
		kfree(i);
	}
L
Linus Torvalds 已提交
2951 2952 2953 2954 2955 2956

done:
	rtnl_unlock();
	return err;
}

2957
static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
L
Linus Torvalds 已提交
2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970
{
	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;
2971 2972
				dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
				if (dev)
L
Linus Torvalds 已提交
2973 2974 2975 2976 2977 2978 2979 2980 2981 2982 2983 2984 2985 2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996
					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;
2997 2998
		dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
		if (dev != NULL)
L
Linus Torvalds 已提交
2999 3000 3001 3002 3003 3004 3005
			packet_dev_mc(dev, ml, -1);
		kfree(ml);
	}
	rtnl_unlock();
}

static int
3006
packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
L
Linus Torvalds 已提交
3007 3008
{
	struct sock *sk = sock->sk;
3009
	struct packet_sock *po = pkt_sk(sk);
L
Linus Torvalds 已提交
3010 3011 3012 3013 3014
	int ret;

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

J
Johann Baudy 已提交
3015
	switch (optname) {
3016
	case PACKET_ADD_MEMBERSHIP:
L
Linus Torvalds 已提交
3017 3018
	case PACKET_DROP_MEMBERSHIP:
	{
3019 3020 3021 3022
		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
3023
			return -EINVAL;
3024 3025
		if (len > sizeof(mreq))
			len = sizeof(mreq);
E
Eric Dumazet 已提交
3026
		if (copy_from_user(&mreq, optval, len))
L
Linus Torvalds 已提交
3027
			return -EFAULT;
3028 3029
		if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
			return -EINVAL;
L
Linus Torvalds 已提交
3030 3031 3032 3033 3034 3035
		if (optname == PACKET_ADD_MEMBERSHIP)
			ret = packet_mc_add(sk, &mreq);
		else
			ret = packet_mc_drop(sk, &mreq);
		return ret;
	}
3036

L
Linus Torvalds 已提交
3037
	case PACKET_RX_RING:
J
Johann Baudy 已提交
3038
	case PACKET_TX_RING:
L
Linus Torvalds 已提交
3039
	{
3040 3041
		union tpacket_req_u req_u;
		int len;
L
Linus Torvalds 已提交
3042

3043 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053
		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
3054
			return -EINVAL;
3055 3056
		if (pkt_sk(sk)->has_vnet_hdr)
			return -EINVAL;
3057
		if (copy_from_user(&req_u.req, optval, len))
L
Linus Torvalds 已提交
3058
			return -EFAULT;
3059 3060
		return packet_set_ring(sk, &req_u, 0,
			optname == PACKET_TX_RING);
L
Linus Torvalds 已提交
3061 3062 3063 3064 3065
	}
	case PACKET_COPY_THRESH:
	{
		int val;

E
Eric Dumazet 已提交
3066
		if (optlen != sizeof(val))
L
Linus Torvalds 已提交
3067
			return -EINVAL;
E
Eric Dumazet 已提交
3068
		if (copy_from_user(&val, optval, sizeof(val)))
L
Linus Torvalds 已提交
3069 3070 3071 3072 3073
			return -EFAULT;

		pkt_sk(sk)->copy_thresh = val;
		return 0;
	}
3074 3075 3076 3077 3078 3079
	case PACKET_VERSION:
	{
		int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3080
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3081 3082 3083 3084 3085 3086
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		switch (val) {
		case TPACKET_V1:
		case TPACKET_V2:
3087
		case TPACKET_V3:
3088 3089 3090 3091 3092 3093
			po->tp_version = val;
			return 0;
		default:
			return -EINVAL;
		}
	}
3094 3095 3096 3097 3098 3099
	case PACKET_RESERVE:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
J
Johann Baudy 已提交
3100
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3101 3102 3103 3104 3105 3106
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_reserve = val;
		return 0;
	}
J
Johann Baudy 已提交
3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119
	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;
	}
3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131
	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;
	}
3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143
	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;
	}
3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159
	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;
	}
3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171
	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
3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182
	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);
	}
3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195
	case PACKET_TX_HAS_OFF:
	{
		unsigned int val;

		if (optlen != sizeof(val))
			return -EINVAL;
		if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
			return -EBUSY;
		if (copy_from_user(&val, optval, sizeof(val)))
			return -EFAULT;
		po->tp_tx_has_off = !!val;
		return 0;
	}
L
Linus Torvalds 已提交
3196 3197 3198 3199 3200 3201 3202 3203 3204
	default:
		return -ENOPROTOOPT;
	}
}

static int packet_getsockopt(struct socket *sock, int level, int optname,
			     char __user *optval, int __user *optlen)
{
	int len;
3205
	int val, lv = sizeof(val);
L
Linus Torvalds 已提交
3206 3207
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
3208
	void *data = &val;
3209
	union tpacket_stats_u st;
L
Linus Torvalds 已提交
3210 3211 3212 3213

	if (level != SOL_PACKET)
		return -ENOPROTOOPT;

3214 3215
	if (get_user(len, optlen))
		return -EFAULT;
L
Linus Torvalds 已提交
3216 3217 3218

	if (len < 0)
		return -EINVAL;
3219

J
Johann Baudy 已提交
3220
	switch (optname) {
L
Linus Torvalds 已提交
3221 3222
	case PACKET_STATISTICS:
		spin_lock_bh(&sk->sk_receive_queue.lock);
3223 3224 3225 3226
		memcpy(&st, &po->stats, sizeof(st));
		memset(&po->stats, 0, sizeof(po->stats));
		spin_unlock_bh(&sk->sk_receive_queue.lock);

3227
		if (po->tp_version == TPACKET_V3) {
3228
			lv = sizeof(struct tpacket_stats_v3);
3229
			st.stats3.tp_packets += st.stats3.tp_drops;
3230
			data = &st.stats3;
3231
		} else {
3232
			lv = sizeof(struct tpacket_stats);
3233
			st.stats1.tp_packets += st.stats1.tp_drops;
3234
			data = &st.stats1;
3235
		}
3236

3237 3238 3239
		break;
	case PACKET_AUXDATA:
		val = po->auxdata;
3240 3241 3242
		break;
	case PACKET_ORIGDEV:
		val = po->origdev;
3243 3244 3245
		break;
	case PACKET_VNET_HDR:
		val = po->has_vnet_hdr;
L
Linus Torvalds 已提交
3246
		break;
3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261
	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;
3262 3263 3264
		case TPACKET_V3:
			val = sizeof(struct tpacket3_hdr);
			break;
3265 3266 3267 3268
		default:
			return -EINVAL;
		}
		break;
3269 3270 3271
	case PACKET_RESERVE:
		val = po->tp_reserve;
		break;
J
Johann Baudy 已提交
3272 3273 3274
	case PACKET_LOSS:
		val = po->tp_loss;
		break;
3275 3276 3277
	case PACKET_TIMESTAMP:
		val = po->tp_tstamp;
		break;
D
David S. Miller 已提交
3278 3279 3280
	case PACKET_FANOUT:
		val = (po->fanout ?
		       ((u32)po->fanout->id |
3281 3282
			((u32)po->fanout->type << 16) |
			((u32)po->fanout->flags << 24)) :
D
David S. Miller 已提交
3283 3284
		       0);
		break;
3285 3286 3287
	case PACKET_TX_HAS_OFF:
		val = po->tp_tx_has_off;
		break;
L
Linus Torvalds 已提交
3288 3289 3290 3291
	default:
		return -ENOPROTOOPT;
	}

3292 3293
	if (len > lv)
		len = lv;
3294 3295
	if (put_user(len, optlen))
		return -EFAULT;
3296 3297
	if (copy_to_user(optval, data, len))
		return -EFAULT;
3298
	return 0;
L
Linus Torvalds 已提交
3299 3300 3301
}


3302 3303
static int packet_notifier(struct notifier_block *this,
			   unsigned long msg, void *ptr)
L
Linus Torvalds 已提交
3304 3305
{
	struct sock *sk;
3306
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3307
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
3308

3309
	rcu_read_lock();
3310
	sk_for_each_rcu(sk, &net->packet.sklist) {
L
Linus Torvalds 已提交
3311 3312 3313 3314 3315 3316
		struct packet_sock *po = pkt_sk(sk);

		switch (msg) {
		case NETDEV_UNREGISTER:
			if (po->mclist)
				packet_dev_mclist(dev, po->mclist, -1);
3317 3318
			/* fallthrough */

L
Linus Torvalds 已提交
3319 3320 3321 3322
		case NETDEV_DOWN:
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
				if (po->running) {
3323
					__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
3324 3325 3326 3327 3328 3329
					sk->sk_err = ENETDOWN;
					if (!sock_flag(sk, SOCK_DEAD))
						sk->sk_error_report(sk);
				}
				if (msg == NETDEV_UNREGISTER) {
					po->ifindex = -1;
3330 3331
					if (po->prot_hook.dev)
						dev_put(po->prot_hook.dev);
L
Linus Torvalds 已提交
3332 3333 3334 3335 3336 3337
					po->prot_hook.dev = NULL;
				}
				spin_unlock(&po->bind_lock);
			}
			break;
		case NETDEV_UP:
3338 3339
			if (dev->ifindex == po->ifindex) {
				spin_lock(&po->bind_lock);
3340 3341
				if (po->num)
					register_prot_hook(sk);
3342
				spin_unlock(&po->bind_lock);
L
Linus Torvalds 已提交
3343 3344 3345 3346
			}
			break;
		}
	}
3347
	rcu_read_unlock();
L
Linus Torvalds 已提交
3348 3349 3350 3351 3352 3353 3354 3355 3356
	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
3357
	switch (cmd) {
E
Eric Dumazet 已提交
3358 3359 3360
	case SIOCOUTQ:
	{
		int amount = sk_wmem_alloc_get(sk);
3361

E
Eric Dumazet 已提交
3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379
		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);
3380

L
Linus Torvalds 已提交
3381
#ifdef CONFIG_INET
E
Eric Dumazet 已提交
3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396
	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
3397 3398
#endif

E
Eric Dumazet 已提交
3399 3400
	default:
		return -ENOIOCTLCMD;
L
Linus Torvalds 已提交
3401 3402 3403 3404
	}
	return 0;
}

E
Eric Dumazet 已提交
3405
static unsigned int packet_poll(struct file *file, struct socket *sock,
L
Linus Torvalds 已提交
3406 3407 3408 3409 3410 3411 3412
				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
3413
	if (po->rx_ring.pg_vec) {
3414 3415
		if (!packet_previous_rx_frame(po, &po->rx_ring,
			TP_STATUS_KERNEL))
L
Linus Torvalds 已提交
3416 3417 3418
			mask |= POLLIN | POLLRDNORM;
	}
	spin_unlock_bh(&sk->sk_receive_queue.lock);
J
Johann Baudy 已提交
3419 3420 3421 3422 3423 3424
	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
3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435
	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
3436
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3437
	struct sock *sk = sock->sk;
3438

L
Linus Torvalds 已提交
3439 3440 3441 3442 3443 3444 3445
	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
3446
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
3447
	struct sock *sk = sock->sk;
3448

L
Linus Torvalds 已提交
3449 3450 3451 3452
	if (sk)
		atomic_dec(&pkt_sk(sk)->mapped);
}

3453
static const struct vm_operations_struct packet_mmap_ops = {
E
Eric Dumazet 已提交
3454 3455
	.open	=	packet_mm_open,
	.close	=	packet_mm_close,
L
Linus Torvalds 已提交
3456 3457
};

3458 3459
static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
			unsigned int len)
L
Linus Torvalds 已提交
3460 3461 3462
{
	int i;

3463
	for (i = 0; i < len; i++) {
3464
		if (likely(pg_vec[i].buffer)) {
C
Changli Gao 已提交
3465
			if (is_vmalloc_addr(pg_vec[i].buffer))
3466 3467 3468 3469 3470 3471
				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
3472 3473 3474 3475
	}
	kfree(pg_vec);
}

3476
static char *alloc_one_pg_vec_page(unsigned long order)
3477
{
3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489
	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
3490
	buffer = vzalloc((1 << order) * PAGE_SIZE);
3491

3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506
	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;
3507 3508
}

3509
static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3510 3511
{
	unsigned int block_nr = req->tp_block_nr;
3512
	struct pgv *pg_vec;
3513 3514
	int i;

3515
	pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3516 3517 3518 3519
	if (unlikely(!pg_vec))
		goto out;

	for (i = 0; i < block_nr; i++) {
C
Changli Gao 已提交
3520
		pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3521
		if (unlikely(!pg_vec[i].buffer))
3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532
			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
3533

3534
static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
J
Johann Baudy 已提交
3535
		int closing, int tx_ring)
L
Linus Torvalds 已提交
3536
{
3537
	struct pgv *pg_vec = NULL;
L
Linus Torvalds 已提交
3538
	struct packet_sock *po = pkt_sk(sk);
A
Al Viro 已提交
3539
	int was_running, order = 0;
J
Johann Baudy 已提交
3540 3541
	struct packet_ring_buffer *rb;
	struct sk_buff_head *rb_queue;
A
Al Viro 已提交
3542
	__be16 num;
3543 3544 3545 3546 3547 3548 3549 3550 3551
	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;
	}
3552

J
Johann Baudy 已提交
3553 3554
	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
3555

J
Johann Baudy 已提交
3556 3557 3558 3559 3560 3561 3562
	err = -EBUSY;
	if (!closing) {
		if (atomic_read(&po->mapped))
			goto out;
		if (atomic_read(&rb->pending))
			goto out;
	}
L
Linus Torvalds 已提交
3563

J
Johann Baudy 已提交
3564 3565 3566 3567 3568
	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
3569

3570 3571 3572 3573 3574 3575 3576
		switch (po->tp_version) {
		case TPACKET_V1:
			po->tp_hdrlen = TPACKET_HDRLEN;
			break;
		case TPACKET_V2:
			po->tp_hdrlen = TPACKET2_HDRLEN;
			break;
3577 3578 3579
		case TPACKET_V3:
			po->tp_hdrlen = TPACKET3_HDRLEN;
			break;
3580 3581
		}

J
Johann Baudy 已提交
3582
		err = -EINVAL;
3583
		if (unlikely((int)req->tp_block_size <= 0))
J
Johann Baudy 已提交
3584
			goto out;
3585
		if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
J
Johann Baudy 已提交
3586
			goto out;
3587
		if (unlikely(req->tp_frame_size < po->tp_hdrlen +
J
Johann Baudy 已提交
3588 3589
					po->tp_reserve))
			goto out;
3590
		if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
J
Johann Baudy 已提交
3591
			goto out;
L
Linus Torvalds 已提交
3592

J
Johann Baudy 已提交
3593 3594 3595 3596 3597 3598
		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
3599 3600

		err = -ENOMEM;
3601 3602 3603
		order = get_order(req->tp_block_size);
		pg_vec = alloc_pg_vec(req, order);
		if (unlikely(!pg_vec))
L
Linus Torvalds 已提交
3604
			goto out;
3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615
		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
3616 3617 3618 3619
	}
	/* Done */
	else {
		err = -EINVAL;
3620
		if (unlikely(req->tp_frame_nr))
J
Johann Baudy 已提交
3621
			goto out;
L
Linus Torvalds 已提交
3622 3623 3624 3625 3626 3627 3628 3629 3630 3631
	}

	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;
3632
		__unregister_prot_hook(sk, false);
L
Linus Torvalds 已提交
3633 3634
	}
	spin_unlock(&po->bind_lock);
3635

L
Linus Torvalds 已提交
3636 3637 3638
	synchronize_net();

	err = -EBUSY;
3639
	mutex_lock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3640 3641
	if (closing || atomic_read(&po->mapped) == 0) {
		err = 0;
J
Johann Baudy 已提交
3642
		spin_lock_bh(&rb_queue->lock);
3643
		swap(rb->pg_vec, pg_vec);
J
Johann Baudy 已提交
3644 3645 3646 3647 3648
		rb->frame_max = (req->tp_frame_nr - 1);
		rb->head = 0;
		rb->frame_size = req->tp_frame_size;
		spin_unlock_bh(&rb_queue->lock);

3649 3650
		swap(rb->pg_vec_order, order);
		swap(rb->pg_vec_len, req->tp_block_nr);
J
Johann Baudy 已提交
3651 3652 3653 3654 3655

		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
3656
		if (atomic_read(&po->mapped))
E
Eric Dumazet 已提交
3657 3658
			pr_err("packet_mmap: vma is busy: %d\n",
			       atomic_read(&po->mapped));
L
Linus Torvalds 已提交
3659
	}
3660
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3661 3662

	spin_lock(&po->bind_lock);
3663
	if (was_running) {
L
Linus Torvalds 已提交
3664
		po->num = num;
3665
		register_prot_hook(sk);
L
Linus Torvalds 已提交
3666 3667
	}
	spin_unlock(&po->bind_lock);
3668 3669 3670 3671 3672
	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
3673 3674 3675 3676 3677 3678 3679 3680
	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
3681 3682
static int packet_mmap(struct file *file, struct socket *sock,
		struct vm_area_struct *vma)
L
Linus Torvalds 已提交
3683 3684 3685
{
	struct sock *sk = sock->sk;
	struct packet_sock *po = pkt_sk(sk);
J
Johann Baudy 已提交
3686 3687
	unsigned long size, expected_size;
	struct packet_ring_buffer *rb;
L
Linus Torvalds 已提交
3688 3689 3690 3691 3692 3693 3694
	unsigned long start;
	int err = -EINVAL;
	int i;

	if (vma->vm_pgoff)
		return -EINVAL;

3695
	mutex_lock(&po->pg_vec_lock);
J
Johann Baudy 已提交
3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706

	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
3707
		goto out;
J
Johann Baudy 已提交
3708 3709 3710

	size = vma->vm_end - vma->vm_start;
	if (size != expected_size)
L
Linus Torvalds 已提交
3711 3712 3713
		goto out;

	start = vma->vm_start;
J
Johann Baudy 已提交
3714 3715 3716 3717 3718
	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++) {
3719 3720
			struct page *page;
			void *kaddr = rb->pg_vec[i].buffer;
J
Johann Baudy 已提交
3721 3722
			int pg_num;

C
Changli Gao 已提交
3723 3724
			for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
				page = pgv_to_page(kaddr);
J
Johann Baudy 已提交
3725 3726 3727 3728
				err = vm_insert_page(vma, start, page);
				if (unlikely(err))
					goto out;
				start += PAGE_SIZE;
3729
				kaddr += PAGE_SIZE;
J
Johann Baudy 已提交
3730
			}
3731
		}
L
Linus Torvalds 已提交
3732
	}
J
Johann Baudy 已提交
3733

3734
	atomic_inc(&po->mapped);
L
Linus Torvalds 已提交
3735 3736 3737 3738
	vma->vm_ops = &packet_mmap_ops;
	err = 0;

out:
3739
	mutex_unlock(&po->pg_vec_lock);
L
Linus Torvalds 已提交
3740 3741 3742
	return err;
}

3743
static const struct proto_ops packet_ops_spkt = {
L
Linus Torvalds 已提交
3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763
	.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,
};

3764
static const struct proto_ops packet_ops = {
L
Linus Torvalds 已提交
3765 3766 3767 3768 3769 3770 3771
	.family =	PF_PACKET,
	.owner =	THIS_MODULE,
	.release =	packet_release,
	.bind =		packet_bind,
	.connect =	sock_no_connect,
	.socketpair =	sock_no_socketpair,
	.accept =	sock_no_accept,
3772
	.getname =	packet_getname,
L
Linus Torvalds 已提交
3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784
	.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,
};

3785
static const struct net_proto_family packet_family_ops = {
L
Linus Torvalds 已提交
3786 3787 3788 3789 3790 3791
	.family =	PF_PACKET,
	.create =	packet_create,
	.owner	=	THIS_MODULE,
};

static struct notifier_block packet_netdev_notifier = {
E
Eric Dumazet 已提交
3792
	.notifier_call =	packet_notifier,
L
Linus Torvalds 已提交
3793 3794 3795 3796 3797
};

#ifdef CONFIG_PROC_FS

static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3798
	__acquires(RCU)
L
Linus Torvalds 已提交
3799
{
3800
	struct net *net = seq_file_net(seq);
3801 3802 3803

	rcu_read_lock();
	return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
L
Linus Torvalds 已提交
3804 3805 3806 3807
}

static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
3808
	struct net *net = seq_file_net(seq);
3809
	return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
L
Linus Torvalds 已提交
3810 3811 3812
}

static void packet_seq_stop(struct seq_file *seq, void *v)
3813
	__releases(RCU)
L
Linus Torvalds 已提交
3814
{
3815
	rcu_read_unlock();
L
Linus Torvalds 已提交
3816 3817
}

3818
static int packet_seq_show(struct seq_file *seq, void *v)
L
Linus Torvalds 已提交
3819 3820 3821 3822
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
	else {
3823
		struct sock *s = sk_entry(v);
L
Linus Torvalds 已提交
3824 3825 3826
		const struct packet_sock *po = pkt_sk(s);

		seq_printf(seq,
D
Dan Rosenberg 已提交
3827
			   "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
L
Linus Torvalds 已提交
3828 3829 3830 3831 3832 3833 3834
			   s,
			   atomic_read(&s->sk_refcnt),
			   s->sk_type,
			   ntohs(po->num),
			   po->ifindex,
			   po->running,
			   atomic_read(&s->sk_rmem_alloc),
3835
			   from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
E
Eric Dumazet 已提交
3836
			   sock_i_ino(s));
L
Linus Torvalds 已提交
3837 3838 3839 3840 3841
	}

	return 0;
}

3842
static const struct seq_operations packet_seq_ops = {
L
Linus Torvalds 已提交
3843 3844 3845 3846 3847 3848 3849 3850
	.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)
{
3851 3852
	return seq_open_net(inode, file, &packet_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
3853 3854
}

3855
static const struct file_operations packet_seq_fops = {
L
Linus Torvalds 已提交
3856 3857 3858 3859
	.owner		= THIS_MODULE,
	.open		= packet_seq_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
3860
	.release	= seq_release_net,
L
Linus Torvalds 已提交
3861 3862 3863 3864
};

#endif

3865
static int __net_init packet_net_init(struct net *net)
3866
{
3867
	mutex_init(&net->packet.sklist_lock);
3868
	INIT_HLIST_HEAD(&net->packet.sklist);
3869

3870
	if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
3871 3872 3873 3874 3875
		return -ENOMEM;

	return 0;
}

3876
static void __net_exit packet_net_exit(struct net *net)
3877
{
3878
	remove_proc_entry("packet", net->proc_net);
3879 3880 3881 3882 3883 3884 3885 3886
}

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


L
Linus Torvalds 已提交
3887 3888 3889
static void __exit packet_exit(void)
{
	unregister_netdevice_notifier(&packet_netdev_notifier);
3890
	unregister_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902
	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);
3903
	register_pernet_subsys(&packet_net_ops);
L
Linus Torvalds 已提交
3904 3905 3906 3907 3908 3909 3910 3911 3912
	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);