sock.h

嵌入式系统设计与实例开发实验教材二源码 多线程应用程序设计 串行端口程序设计 AD接口实验 CAN总线通信实验 GPS通信实验 Linux内核移植与编译实验 IC卡读写实验 SD驱动使

/*
 * 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.
 *
 *		Definitions for the AF_INET socket handler.
 *
 * Version:	@(#)sock.h	1.0.4	05/13/93
 *
 * Authors:	Ross Biro, <[e-mail]>
 *		Fred N. van Kempen, <[e-mail]>
 *		Corey Minyard <wf-rch![e-mail]>
 *		Florian La Roche <[e-mail]>
 *
 * Fixes:
 *		Alan Cox	:	Volatiles in skbuff pointers. See
 *					skbuff comments. May be overdone,
 *					better to prove they can be removed
 *					than the reverse.
 *		Alan Cox	:	Added a zapped field for tcp to note
 *					a socket is reset and must stay shut up
 *		Alan Cox	:	New fields for options
 *	Pauline Middelink	:	identd support
 *		Alan Cox	:	Eliminate low level recv/recvfrom
 *		David S. Miller	:	New socket lookup architecture.
 *              Steve Whitehouse:       Default routines for sock_ops
 *
 *		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.
 */
#ifndef _SOCK_H
#define _SOCK_H

#include <linux/config.h>
#include <linux/timer.h>
#include <linux/cache.h>
#include <linux/in.h>		/* struct sockaddr_in */

#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
#include <linux/in6.h>		/* struct sockaddr_in6 */
#include <linux/ipv6.h>		/* dest_cache, inet6_options */
#include <linux/icmpv6.h>
#include <net/if_inet6.h>	/* struct ipv6_mc_socklist */
#endif

#if defined(CONFIG_INET) || defined (CONFIG_INET_MODULE)
#include <linux/icmp.h>
#endif
#include <linux/tcp.h>		/* struct tcphdr */

#include <linux/netdevice.h>
#include <linux/skbuff.h>	/* struct sk_buff */
#include <net/protocol.h>		/* struct inet_protocol */
#if defined(CONFIG_X25) || defined(CONFIG_X25_MODULE)
#include <net/x25.h>
#endif
#if defined(CONFIG_WAN_ROUTER) || defined(CONFIG_WAN_ROUTER_MODULE)
#include <linux/if_wanpipe.h>
#endif

#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
#include <net/ax25.h>
#if defined(CONFIG_NETROM) || defined(CONFIG_NETROM_MODULE)
#include <net/netrom.h>
#endif
#if defined(CONFIG_ROSE) || defined(CONFIG_ROSE_MODULE)
#include <net/rose.h>
#endif
#endif

#if defined(CONFIG_PPPOE) || defined(CONFIG_PPPOE_MODULE)
#include <linux/if_pppox.h>
#include <linux/ppp_channel.h>   /* struct ppp_channel */
#endif

#if defined(CONFIG_IPX) || defined(CONFIG_IPX_MODULE)
#if defined(CONFIG_SPX) || defined(CONFIG_SPX_MODULE)
#include <net/spx.h>
#else
#include <net/ipx.h>
#endif /* CONFIG_SPX */
#endif /* CONFIG_IPX */

#if defined(CONFIG_ATALK) || defined(CONFIG_ATALK_MODULE)
#include <linux/atalk.h>
#endif

#if defined(CONFIG_DECNET) || defined(CONFIG_DECNET_MODULE)
#include <net/dn.h>
#endif

#if defined(CONFIG_IRDA) || defined(CONFIG_IRDA_MODULE)
#include <net/irda/irda.h>
#endif

#if defined(CONFIG_ATM) || defined(CONFIG_ATM_MODULE)
struct atm_vcc;
#endif

#ifdef CONFIG_FILTER
#include <linux/filter.h>
#endif

#include <asm/atomic.h>
#include <net/dst.h>


/* The AF_UNIX specific socket options */
struct unix_opt {
	struct unix_address	*addr;
	struct dentry *		dentry;
	struct vfsmount *	mnt;
	struct semaphore	readsem;
	struct sock *		other;
	struct sock **		list;
	struct sock *		gc_tree;
	atomic_t		inflight;
	rwlock_t		lock;
	wait_queue_head_t	peer_wait;
};


/* Once the IPX ncpd patches are in these are going into protinfo. */
#if defined(CONFIG_IPX) || defined(CONFIG_IPX_MODULE)
struct ipx_opt {
	ipx_address		dest_addr;
	ipx_interface		*intrfc;
	unsigned short		port;
#ifdef CONFIG_IPX_INTERN
	unsigned char           node[IPX_NODE_LEN];
#endif
	unsigned short		type;
/* 
 * To handle special ncp connection-handling sockets for mars_nwe,
 * the connection number must be stored in the socket.
 */
	unsigned short		ipx_ncp_conn;
};
#endif

#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
struct ipv6_pinfo {
	struct in6_addr 	saddr;
	struct in6_addr 	rcv_saddr;
	struct in6_addr		daddr;
	struct in6_addr		*daddr_cache;

	__u32			flow_label;
	__u32			frag_size;
	int			hop_limit;
	int			mcast_hops;
	int			mcast_oif;

	/* pktoption flags */
	union {
		struct {
			__u8	srcrt:2,
			        rxinfo:1,
				rxhlim:1,
				hopopts:1,
				dstopts:1,
                                authhdr:1,
                                rxflow:1;
		} bits;
		__u8		all;
	} rxopt;

	/* sockopt flags */
	__u8			mc_loop:1,
	                        recverr:1,
	                        sndflow:1,
	                        pmtudisc:2;

	struct ipv6_mc_socklist	*ipv6_mc_list;
	struct ipv6_fl_socklist *ipv6_fl_list;
	__u32			dst_cookie;

	struct ipv6_txoptions	*opt;
	struct sk_buff		*pktoptions;
};

struct raw6_opt {
	__u32			checksum;	/* perform checksum */
	__u32			offset;		/* checksum offset  */

	struct icmp6_filter	filter;
};

#endif /* IPV6 */

#if defined(CONFIG_INET) || defined(CONFIG_INET_MODULE)
struct raw_opt {
	struct icmp_filter	filter;
};
#endif

#if defined(CONFIG_INET) || defined (CONFIG_INET_MODULE)
struct inet_opt
{
	int			ttl;			/* TTL setting */
	int			tos;			/* TOS */
	unsigned	   	cmsg_flags;
	struct ip_options	*opt;
	unsigned char		hdrincl;		/* Include headers ? */
	__u8			mc_ttl;			/* Multicasting TTL */
	__u8			mc_loop;		/* Loopback */
	unsigned		recverr : 1,
				freebind : 1;
	__u16			id;			/* ID counter for DF pkts */
	__u8			pmtudisc;
	int			mc_index;		/* Multicast device index */
	__u32			mc_addr;
	struct ip_mc_socklist	*mc_list;		/* Group array */
};
#endif

#if defined(CONFIG_PPPOE) || defined (CONFIG_PPPOE_MODULE)
struct pppoe_opt
{
	struct net_device      *dev;	  /* device associated with socket*/
	struct pppoe_addr	pa;	  /* what this socket is bound to*/
	struct sockaddr_pppox	relay;	  /* what socket data will be
					     relayed to (PPPoE relaying) */
};

struct pppox_opt
{
	struct ppp_channel	chan;
	struct sock		*sk;
	struct pppox_opt	*next;	  /* for hash table */
	union {
		struct pppoe_opt pppoe;
	} proto;
};
#define pppoe_dev	proto.pppoe.dev
#define pppoe_pa	proto.pppoe.pa
#define pppoe_relay	proto.pppoe.relay
#endif

/* This defines a selective acknowledgement block. */
struct tcp_sack_block {
	__u32	start_seq;
	__u32	end_seq;
};

struct tcp_opt {
	int	tcp_header_len;	/* Bytes of tcp header to send		*/

/*
 *	Header prediction flags
 *	0x5?10 << 16 + snd_wnd in net byte order
 */
	__u32	pred_flags;

/*
 *	RFC793 variables by their proper names. This means you can
 *	read the code and the spec side by side (and laugh ...)
 *	See RFC793 and RFC1122. The RFC writes these in capitals.
 */
 	__u32	rcv_nxt;	/* What we want to receive next 	*/
 	__u32	snd_nxt;	/* Next sequence we send		*/

 	__u32	snd_una;	/* First byte we want an ack for	*/
 	__u32	snd_sml;	/* Last byte of the most recently transmitted small packet */
	__u32	rcv_tstamp;	/* timestamp of last received ACK (for keepalives) */
	__u32	lsndtime;	/* timestamp of last sent data packet (for restart window) */

	/* Delayed ACK control data */
	struct {
		__u8	pending;	/* ACK is pending */
		__u8	quick;		/* Scheduled number of quick acks	*/
		__u8	pingpong;	/* The session is interactive		*/
		__u8	blocked;	/* Delayed ACK was blocked by socket lock*/
		__u32	ato;		/* Predicted tick of soft clock		*/
		unsigned long timeout;	/* Currently scheduled timeout		*/
		__u32	lrcvtime;	/* timestamp of last received data packet*/
		__u16	last_seg_size;	/* Size of last incoming segment	*/
		__u16	rcv_mss;	/* MSS used for delayed ACK decisions	*/ 
	} ack;

	/* Data for direct copy to user */
	struct {
		struct sk_buff_head	prequeue;
		int			memory;
		struct task_struct	*task;
		struct iovec		*iov;
		int			len;
	} ucopy;

	__u32	snd_wl1;	/* Sequence for window update		*/
	__u32	snd_wnd;	/* The window we expect to receive	*/
	__u32	max_window;	/* Maximal window ever seen from peer	*/
	__u32	pmtu_cookie;	/* Last pmtu seen by socket		*/
	__u16	mss_cache;	/* Cached effective mss, not including SACKS */
	__u16	mss_clamp;	/* Maximal mss, negotiated at connection setup */
	__u16	ext_header_len;	/* Network protocol overhead (IP/IPv6 options) */
	__u8	ca_state;	/* State of fast-retransmit machine 	*/
	__u8	retransmits;	/* Number of unrecovered RTO timeouts.	*/

	__u8	reordering;	/* Packet reordering metric.		*/
	__u8	queue_shrunk;	/* Write queue has been shrunk recently.*/
	__u8	defer_accept;	/* User waits for some data after accept() */

/* RTT measurement */
	__u8	backoff;	/* backoff				*/
	__u32	srtt;		/* smothed round trip time << 3		*/
	__u32	mdev;		/* medium deviation			*/
	__u32	mdev_max;	/* maximal mdev for the last rtt period	*/
	__u32	rttvar;		/* smoothed mdev_max			*/
	__u32	rtt_seq;	/* sequence number to update rttvar	*/
	__u32	rto;		/* retransmit timeout			*/

	__u32	packets_out;	/* Packets which are "in flight"	*/
	__u32	left_out;	/* Packets which leaved network		*/
	__u32	retrans_out;	/* Retransmitted packets out		*/


/*
 *	Slow start and congestion control (see also Nagle, and Karn & Partridge)
 */
 	__u32	snd_ssthresh;	/* Slow start size threshold		*/
 	__u32	snd_cwnd;	/* Sending congestion window		*/
 	__u16	snd_cwnd_cnt;	/* Linear increase counter		*/
	__u16	snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */
	__u32	snd_cwnd_used;
	__u32	snd_cwnd_stamp;

	/* Two commonly used timers in both sender and receiver paths. */
	unsigned long		timeout;
 	struct timer_list	retransmit_timer;	/* Resend (no ack)	*/
 	struct timer_list	delack_timer;		/* Ack delay 		*/

	struct sk_buff_head	out_of_order_queue; /* Out of order segments go here */

	struct tcp_func		*af_specific;	/* Operations which are AF_INET{4,6} specific	*/
	struct sk_buff		*send_head;	/* Front of stuff to transmit			*/
	struct page		*sndmsg_page;	/* Cached page for sendmsg			*/
	u32			sndmsg_off;	/* Cached offset for sendmsg			*/

 	__u32	rcv_wnd;	/* Current receiver window		*/
	__u32	rcv_wup;	/* rcv_nxt on last window update sent	*/
	__u32	write_seq;	/* Tail(+1) of data held in tcp send buffer */
	__u32	pushed_seq;	/* Last pushed seq, required to talk to windows */
	__u32	copied_seq;	/* Head of yet unread data		*/
/*
 *      Options received (usually on last packet, some only on SYN packets).
 */
	char	tstamp_ok,	/* TIMESTAMP seen on SYN packet		*/
		wscale_ok,	/* Wscale seen on SYN packet		*/
		sack_ok;	/* SACK seen on SYN packet		*/
	char	saw_tstamp;	/* Saw TIMESTAMP on last packet		*/
        __u8	snd_wscale;	/* Window scaling received from sender	*/
        __u8	rcv_wscale;	/* Window scaling to send to receiver	*/
	__u8	nonagle;	/* Disable Nagle algorithm?             */
	__u8	keepalive_probes; /* num of allowed keep alive probes	*/

/*	PAWS/RTTM data	*/
        __u32	rcv_tsval;	/* Time stamp value             	*/
        __u32	rcv_tsecr;	/* Time stamp echo reply        	*/
        __u32	ts_recent;	/* Time stamp to echo next		*/
        long	ts_recent_stamp;/* Time we stored ts_recent (for aging) */

/*	SACKs data	*/
	__u16	user_mss;  	/* mss requested by user in ioctl */
	__u8	dsack;		/* D-SACK is scheduled			*/
	__u8	eff_sacks;	/* Size of SACK array to send with next packet */
	struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */
	struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/

	__u32	window_clamp;	/* Maximal window to advertise		*/
	__u32	rcv_ssthresh;	/* Current window clamp			*/
	__u8	probes_out;	/* unanswered 0 window probes		*/
	__u8	num_sacks;	/* Number of SACK blocks		*/
	__u16	advmss;		/* Advertised MSS			*/

	__u8	syn_retries;	/* num of allowed syn retries */
	__u8	ecn_flags;	/* ECN status bits.			*/
	__u16	prior_ssthresh; /* ssthresh saved at recovery start	*/
	__u32	lost_out;	/* Lost packets				*/
	__u32	sacked_out;	/* SACK'd packets			*/
	__u32	fackets_out;	/* FACK'd packets			*/
	__u32	high_seq;	/* snd_nxt at onset of congestion	*/

	__u32	retrans_stamp;	/* Timestamp of the last retransmit,
				 * also used in SYN-SENT to remember stamp of
				 * the first SYN. */
	__u32	undo_marker;	/* tracking retrans started here. */
	int	undo_retrans;	/* number of undoable retransmissions. */
	__u32	urg_seq;	/* Seq of received urgent pointer */
	__u16	urg_data;	/* Saved octet of OOB data and control flags */
	__u8	pending;	/* Scheduled timer event	*/
	__u8	urg_mode;	/* In urgent mode		*/
	__u32	snd_up;		/* Urgent pointer		*/

	/* The syn_wait_lock is necessary only to avoid tcp_get_info having
	 * to grab the main lock sock while browsing the listening hash
	 * (otherwise it's deadlock prone).
	 * This lock is acquired in read mode only from tcp_get_info() and
	 * it's acquired in write mode _only_ from code that is actively
	 * changing the syn_wait_queue. All readers that are holding
	 * the master sock lock don't need to grab this lock in read mode
	 * too as the syn_wait_queue writes are always protected from
	 * the main sock lock.
	 */
	rwlock_t		syn_wait_lock;
	struct tcp_listen_opt	*listen_opt;

	/* FIFO of established children */
	struct open_request	*accept_queue;
	struct open_request	*accept_queue_tail;

	int			write_pending;	/* A write to socket waits to start. */

	unsigned int		keepalive_time;	  /* time before keep alive takes place */
	unsigned int		keepalive_intvl;  /* time interval between keep alive probes */
	int			linger2;

	unsigned long last_synq_overflow; 
};

 	
/*
 * This structure really needs to be cleaned up.
 * Most of it is for TCP, and not used by any of
 * the other protocols.
 */

/*
 * The idea is to start moving to a newer struct gradualy
 * 
 * IMHO the newer struct should have the following format:
 * 
 *	struct sock {
 *		sockmem [mem, proto, callbacks]