1 /* $NetBSD: tcp_seq.h,v 1.9 1998/01/05 10:32:07 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1993, 1995 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)tcp_seq.h 8.3 (Berkeley) 6/21/95 36 */ 37 38 /* 39 * TCP sequence numbers are 32 bit integers operated 40 * on with modular arithmetic. These macros can be 41 * used to compare such integers. 42 */ 43 #define SEQ_LT(a,b) ((int)((a)-(b)) < 0) 44 #define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) 45 #define SEQ_GT(a,b) ((int)((a)-(b)) > 0) 46 #define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) 47 48 /* 49 * Macros to initialize tcp sequence numbers for 50 * send and receive from initial send and receive 51 * sequence numbers. 52 */ 53 #define tcp_rcvseqinit(tp) \ 54 (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 55 56 #define tcp_sendseqinit(tp) \ 57 (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \ 58 (tp)->iss 59 60 #define TCP_ISS_RANDOM_MASK 0x0003ffff /* bits of randomness in a TCP ISS */ 61 #define TCP_ISSINCR 0x00040000 /* increment per time and per conn */ 62 63 #ifdef _KERNEL 64 extern tcp_seq tcp_iss_seq; /* tcp initial seq # */ 65 #endif 66