net/tcp/tcp.h

/* */
This source file includes following definitions.
before
after
between
tcp_connected
   1 /* tcp.h */
   2 /*
   3     Copyright (C) 1992  Ross Biro
   4 
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2, or (at your option)
   8     any later version.
   9 
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14 
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
  18 
  19     The Author may be reached as bir7@leland.stanford.edu or
  20     C/O Department of Mathematics; Stanford University; Stanford, CA 94305
  21 */
  22 /* $Id: tcp.h,v 0.8.4.7 1993/01/22 22:58:08 bir7 Exp $ */
  23 /* $Log: tcp.h,v $
  24  * Revision 0.8.4.7  1993/01/22  22:58:08  bir7
  25  * Check in for merge with previous .99 pl 4.
  26  *
  27  * Revision 0.8.4.6  1992/12/12  19:25:04  bir7
  28  * Fixed anti-memory Leak in shutdown.
  29  *
  30  * Revision 0.8.4.5  1992/12/12  01:50:49  bir7
  31  * Fixed several bugs including half-duplex connections.
  32  *
  33  * Revision 0.8.4.4  1992/12/08  20:49:15  bir7
  34  * Fixed minor bugs and checked out MSS.
  35  *
  36  * Revision 0.8.4.3  1992/12/06  23:29:59  bir7
  37  * Added support for mss and half completed packets.  Also added
  38  * support for shrinking windows.
  39  *
  40  * Revision 0.8.4.2  1992/12/03  19:54:12  bir7
  41  * Added paranoid queue checking.
  42  *
  43  * Revision 0.8.4.1  1992/11/10  00:17:18  bir7
  44  * version change only.
  45  *
  46  * Revision 0.8.3.2  1992/11/10  00:14:47  bir7
  47  * Changed malloc to kmalloc and added Id and Log
  48  *
  49  */
  50 
  51 #ifndef _TCP_TCP_H
  52 #define _TCP_TCP_H
  53 
  54 struct tcp_header
  55 {
  56   unsigned short source;
  57   unsigned short dest;
  58   unsigned long seq;
  59   unsigned long ack_seq;
  60   unsigned short res1:4, doff:4, fin:1, syn:1, rst:1, psh:1,
  61                  ack:1, urg:1,res2:2;
  62   unsigned short window;
  63   unsigned short check;
  64   unsigned short urg_ptr;
  65 };
  66 
  67 enum {
  68   TCP_ESTABLISHED=1,
  69   TCP_SYN_SENT,
  70   TCP_SYN_RECV,
  71 #if 0
  72   TCP_CLOSING, /* not a valid state, just a seperator so we can use
  73                   < tcp_closing or > tcp_closing for checks. */
  74 #endif
  75   TCP_FIN_WAIT1,
  76   TCP_FIN_WAIT2,
  77   TCP_TIME_WAIT,
  78   TCP_CLOSE,
  79   TCP_CLOSE_WAIT,
  80   TCP_LAST_ACK,
  81   TCP_LISTEN
  82 };
  83 
  84 #define MAX_SYN_SIZE 44 + sizeof (struct sk_buff) + MAX_HEADER
  85 #define MAX_FIN_SIZE 40 + sizeof (struct sk_buff) + MAX_HEADER
  86 #define MAX_ACK_SIZE 40 + sizeof (struct sk_buff) + MAX_HEADER
  87 #define MAX_RESET_SIZE 40 + sizeof (struct sk_buff) + MAX_HEADER
  88 #define MAX_WINDOW  12000
  89 #define MIN_WINDOW   2048
  90 #define MAX_ACK_BACKLOG 2
  91 #define MIN_WRITE_SPACE 2048
  92 #define TCP_WINDOW_DIFF 2048
  93 
  94 #define TCP_RETR1      10       /* this is howmany retries it does
  95                                    before it tries to figure out
  96                                    if the gateway is down. */
  97 
  98 #define TCP_RETR2      25       /* this should take at least
  99                                    90 minutes to time out. */
 100 
 101 
 102 #define TCP_TIMEOUT_LEN 720000 /* should be about 2 hrs. */
 103 #define TCP_TIMEWAIT_LEN 6000 /* How long to wait to sucessfully 
 104                                  close the socket, about 60 seconds. */
 105 #define TCP_ACK_TIME 35 /* time to delay before sending an ack. */
 106 #define TCP_DONE_TIME 250 /* maximum time to wait before actually destroying
 107                              a socket. */
 108 #define TCP_WRITE_TIME 100 /* initial time to wait for an ack,
 109                               after last transmit. */
 110 #define TCP_CONNECT_TIME 200 /* time to retransmit first syn. */
 111 #define TCP_SYN_RETRIES 30 /* number of times to retry openning a connection.
 112                               */
 113 #define TCP_PROBEWAIT_LEN 250 /* time to wait between probes when I've got
 114                                  something to write and there is no window. */
 115 
 116 #define TCP_NO_CHECK 0 /* turn to one if you want the default to be no
 117                           checksum . */
 118 
 119 void print_th (struct tcp_header *);
 120 #define HEADER_SIZE 64 /* Maximum header size we need to deal with. */
 121 
 122 #define TCP_WRITE_QUEUE_MAGIC 0xa5f23477
 123 
 124  /* this next routines deal with comparing 32 bit unsigned ints and
 125     worry about wrap around. The general strategy is to do a normal
 126     compare so long as neither of the numbers is within 4k of wrapping.
 127     Otherwise we must check for the wrap. */
 128 
 129  static inline int
 130  before (unsigned long seq1, unsigned long seq2)
     /*  */
 131  {
 132    /* this inequality is strict. */
 133    if (seq1 == seq2) return (0);
 134    if (seq1 < seq2) 
 135      {
 136        if ((unsigned long)seq2-(unsigned long)seq1 < 32767UL) 
 137          {
 138            return (1);
 139          }
 140        else
 141          {
 142            return (0);
 143          }
 144      }
 145    /* now we know seq1 > seq2.  So all we need to do is check to see
 146       if seq1 has wrapped. */
 147    if (seq2 < 4096UL && seq1 > (0xffffffUL - 4096UL))
 148      {
 149        return (1);
 150      }
 151    return (0);
 152 
 153  }
 154 
 155  static inline int
 156  after (unsigned long seq1, unsigned long seq2)
     /*  */
 157  {
 158    return (before (seq2, seq1));
 159  }
 160 
 161  /* is s2<=s1<=s3 ? */
 162  static inline int
 163  between (unsigned long seq1, unsigned long seq2, unsigned long seq3)
     /*  */
 164  {
 165    return (after (seq1+1, seq2) && before (seq1, seq3+1));
 166  }
 167 
 168 static inline const int
 169 tcp_connected (const int state)
     /*  */
 170 {
 171   return (state == TCP_ESTABLISHED || state == TCP_CLOSE_WAIT ||
 172           state == TCP_FIN_WAIT1   || state == TCP_FIN_WAIT2);
 173 }
 174 
 175 #endif
/* */
root/net/tcp/tcp.h

INCLUDED FROM

DEFINITIONS
