tcp_seq.h revision 231767
1139823Simp/*- 211150Swollman * Copyright (c) 1982, 1986, 1993, 1995 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * Redistribution and use in source and binary forms, with or without 61541Srgrimes * modification, are permitted provided that the following conditions 71541Srgrimes * are met: 81541Srgrimes * 1. Redistributions of source code must retain the above copyright 91541Srgrimes * notice, this list of conditions and the following disclaimer. 101541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111541Srgrimes * notice, this list of conditions and the following disclaimer in the 121541Srgrimes * documentation and/or other materials provided with the distribution. 131541Srgrimes * 4. Neither the name of the University nor the names of its contributors 141541Srgrimes * may be used to endorse or promote products derived from this software 151541Srgrimes * without specific prior written permission. 161541Srgrimes * 171541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 181541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 191541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 201541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 211541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 221541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 231541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 241541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 251541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 261541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 271541Srgrimes * SUCH DAMAGE. 281541Srgrimes * 2911150Swollman * @(#)tcp_seq.h 8.3 (Berkeley) 6/21/95 3050477Speter * $FreeBSD: head/sys/netinet/tcp_seq.h 231767 2012-02-15 16:09:56Z bz $ 311541Srgrimes */ 321541Srgrimes 332169Spaul#ifndef _NETINET_TCP_SEQ_H_ 342169Spaul#define _NETINET_TCP_SEQ_H_ 351541Srgrimes/* 361541Srgrimes * TCP sequence numbers are 32 bit integers operated 371541Srgrimes * on with modular arithmetic. These macros can be 381541Srgrimes * used to compare such integers. 391541Srgrimes */ 401541Srgrimes#define SEQ_LT(a,b) ((int)((a)-(b)) < 0) 411541Srgrimes#define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) 421541Srgrimes#define SEQ_GT(a,b) ((int)((a)-(b)) > 0) 431541Srgrimes#define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) 441541Srgrimes 45130989Sps#define SEQ_MIN(a, b) ((SEQ_LT(a, b)) ? (a) : (b)) 46130989Sps#define SEQ_MAX(a, b) ((SEQ_GT(a, b)) ? (a) : (b)) 47130989Sps 486247Swollman/* for modulo comparisons of timestamps */ 496247Swollman#define TSTMP_LT(a,b) ((int)((a)-(b)) < 0) 50144858Sps#define TSTMP_GT(a,b) ((int)((a)-(b)) > 0) 516247Swollman#define TSTMP_GEQ(a,b) ((int)((a)-(b)) >= 0) 526247Swollman 531541Srgrimes/* 541541Srgrimes * Macros to initialize tcp sequence numbers for 551541Srgrimes * send and receive from initial send and receive 561541Srgrimes * sequence numbers. 571541Srgrimes */ 581541Srgrimes#define tcp_rcvseqinit(tp) \ 591541Srgrimes (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 601541Srgrimes 611541Srgrimes#define tcp_sendseqinit(tp) \ 621541Srgrimes (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \ 63117650Shsu (tp)->snd_recover = (tp)->iss 641541Srgrimes 65231767Sbz#ifdef _KERNEL 66231767Sbz/* 67231767Sbz * Clock macros for RFC 1323 timestamps. 68231767Sbz */ 69231767Sbz#define TCP_TS_TO_TICKS(_t) ((_t) * hz / 1000) 706247Swollman 71231767Sbz/* Timestamp wrap-around time, 24 days. */ 72231767Sbz#define TCP_PAWS_IDLE (24 * 24 * 60 * 60 * 1000) 73231767Sbz 74231767Sbz/* 75231767Sbz * tcp_ts_getticks() in ms, should be 1ms < x < 1000ms according to RFC 1323. 76231767Sbz * We always use 1ms granularity independent of hz. 77231767Sbz */ 78231767Sbzstatic __inline u_int 79231767Sbztcp_ts_getticks(void) 80231767Sbz{ 81231767Sbz struct timeval tv; 82231767Sbz u_long ms; 83231767Sbz 84231767Sbz /* 85231767Sbz * getmicrouptime() should be good enough for any 1-1000ms granularity. 86231767Sbz * Do not use getmicrotime() here as it might break nfsroot/tcp. 87231767Sbz */ 88231767Sbz getmicrouptime(&tv); 89231767Sbz ms = tv.tv_sec * 1000 + tv.tv_usec / 1000; 90231767Sbz 91231767Sbz return (ms); 92231767Sbz} 93231767Sbz#endif /* _KERNEL */ 94231767Sbz 9511150Swollman#endif /* _NETINET_TCP_SEQ_H_ */ 96