sys/netinet/tcp_seq.h

   1 /*
   2  * Copyright (c) 2003, 2004 Jeffrey M. Hsu.  All rights reserved.
   3  * Copyright (c) 2003, 2004 The DragonFly Project.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to The DragonFly Project
   6  * by Jeffrey M. Hsu.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of The DragonFly Project nor the names of its
  17  *    contributors may be used to endorse or promote products derived
  18  *    from this software without specific, prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  30  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Copyright (c) 2003, 2004 Jeffrey M. Hsu.  All rights reserved.
  36  *
  37  * License terms: all terms for the DragonFly license above plus the following:
  38  *
  39  * 4. All advertising materials mentioning features or use of this software
  40  *    must display the following acknowledgement:
  41  *
  42  *      This product includes software developed by Jeffrey M. Hsu
  43  *      for the DragonFly Project.
  44  *
  45  *    This requirement may be waived with permission from Jeffrey Hsu.
  46  *    This requirement will sunset and may be removed on July 8 2005,
  47  *    after which the standard DragonFly license (as shown above) will
  48  *    apply.
  49  */
  50
  51 /*
  52  * Copyright (c) 1982, 1986, 1993, 1995
  53  *      The Regents of the University of California.  All rights reserved.
  54  *
  55  * Redistribution and use in source and binary forms, with or without
  56  * modification, are permitted provided that the following conditions
  57  * are met:
  58  * 1. Redistributions of source code must retain the above copyright
  59  *    notice, this list of conditions and the following disclaimer.
  60  * 2. Redistributions in binary form must reproduce the above copyright
  61  *    notice, this list of conditions and the following disclaimer in the
  62  *    documentation and/or other materials provided with the distribution.
  63  * 3. All advertising materials mentioning features or use of this software
  64  *    must display the following acknowledgement:
  65  *      This product includes software developed by the University of
  66  *      California, Berkeley and its contributors.
  67  * 4. Neither the name of the University nor the names of its contributors
  68  *    may be used to endorse or promote products derived from this software
  69  *    without specific prior written permission.
  70  *
  71  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  72  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  73  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  74  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  75  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  76  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  77  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  78  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  79  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  80  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  81  * SUCH DAMAGE.
  82  *
  83  *      @(#)tcp_seq.h   8.3 (Berkeley) 6/21/95
  84  * $FreeBSD: src/sys/netinet/tcp_seq.h,v 1.11.2.7 2003/02/03 02:33:10 hsu Exp $
  85  * $DragonFly: src/sys/netinet/tcp_seq.h,v 1.7 2004/12/21 02:54:15 hsu Exp $
  86  */
  87
  88 #ifndef _NETINET_TCP_SEQ_H_
  89 #define _NETINET_TCP_SEQ_H_
  90 /*
  91  * TCP sequence numbers are 32 bit integers operated
  92  * on with modular arithmetic.  These macros can be
  93  * used to compare such integers.
  94  */
  95 #define SEQ_LT(a,b)     ((int)((a)-(b)) < 0)
  96 #define SEQ_LEQ(a,b)    ((int)((a)-(b)) <= 0)
  97 #define SEQ_GT(a,b)     ((int)((a)-(b)) > 0)
  98 #define SEQ_GEQ(a,b)    ((int)((a)-(b)) >= 0)
  99
 100 static __inline tcp_seq
 101 seq_max(tcp_seq a, tcp_seq b)
 102 {
 103         return (SEQ_GT(a, b) ? a : b);
 104 }
 105
 106 static __inline tcp_seq
 107 seq_min(tcp_seq a, tcp_seq b)
 108 {
 109         return (SEQ_LT(a, b) ? a : b);
 110 }
 111
 112 /* for modulo comparisons of timestamps */
 113 #define TSTMP_LT(a,b)   ((int)((a)-(b)) < 0)
 114 #define TSTMP_GEQ(a,b)  ((int)((a)-(b)) >= 0)
 115
 116 /*
 117  * TCP connection counts are 32 bit integers operated
 118  * on with modular arithmetic.  These macros can be
 119  * used to compare such integers.
 120  */
 121 #define CC_LT(a,b)      ((int)((a)-(b)) < 0)
 122 #define CC_LEQ(a,b)     ((int)((a)-(b)) <= 0)
 123 #define CC_GT(a,b)      ((int)((a)-(b)) > 0)
 124 #define CC_GEQ(a,b)     ((int)((a)-(b)) >= 0)
 125
 126 /* Macro to increment a CC: skip 0 which has a special meaning */
 127 #define CC_INC(c)       (++(c) == 0 ? ++(c) : (c))
 128
 129 /*
 130  * Macros to initialize tcp sequence numbers for
 131  * send and receive from initial send and receive
 132  * sequence numbers.
 133  */
 134 #define tcp_rcvseqinit(tp) \
 135         (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1
 136
 137 #define tcp_sendseqinit(tp) \
 138         (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \
 139             (tp)->snd_recover = (tp)->iss
 140
 141 #define TCP_PAWS_IDLE   (24 * 24 * 60 * 60 * hz)
 142                                         /* timestamp wrap-around time */
 143
 144 #ifdef _KERNEL
 145 extern tcp_cc   tcp_ccgen;              /* global connection count */
 146 #endif /* _KERNEL */
 147 #endif /* _NETINET_TCP_SEQ_H_ */