1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#ifndef _NETINET_TCP_SEQ_H_
33#define _NETINET_TCP_SEQ_H_
34/*
35 * TCP sequence numbers are 32 bit integers operated
36 * on with modular arithmetic. These macros can be
37 * used to compare such integers.
38 */
39#define SEQ_LT(a,b) ((int)((a)-(b)) < 0)
40#define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0)
41#define SEQ_GT(a,b) ((int)((a)-(b)) > 0)
42#define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0)
43#define SEQ_SUB(a,b) ((int)((a)-(b)))
44
45#define SEQ_MIN(a, b) ((SEQ_LT(a, b)) ? (a) : (b))
46#define SEQ_MAX(a, b) ((SEQ_GT(a, b)) ? (a) : (b))
47
48#define WIN_LT(a,b) (ntohs(a) < ntohs(b))
49#define WIN_LEQ(a,b) (ntohs(a) <= ntohs(b))
50#define WIN_GT(a,b) (ntohs(a) > ntohs(b))
51#define WIN_GEQ(a,b) (ntohs(a) >= ntohs(b))
52
53#define WIN_MIN(a, b) ((WIN_LT(a, b)) ? (a) : (b))
54#define WIN_MAX(a, b) ((WIN_GT(a, b)) ? (a) : (b))
55
56/* for modulo comparisons of timestamps */
57#define TSTMP_LT(a,b) ((int)((a)-(b)) < 0)
58#define TSTMP_GT(a,b) ((int)((a)-(b)) > 0)
59#define TSTMP_GEQ(a,b) ((int)((a)-(b)) >= 0)
60
61/*
62 * Macros to initialize tcp sequence numbers for
63 * send and receive from initial send and receive
64 * sequence numbers.
65 */
66#define tcp_rcvseqinit(tp) \
67 (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1
68
69#define tcp_sendseqinit(tp) \
70 (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \
71 (tp)->snd_recover = (tp)->iss
72
73#ifdef _KERNEL
74/*
75 * Clock macros for RFC 1323 timestamps.
76 */
77#define TCP_TS_TO_TICKS(_t) ((_t) * hz / 1000)
78
79/* Timestamp wrap-around time, 24 days. */
80#define TCP_PAWS_IDLE (24 * 24 * 60 * 60 * 1000)
81
82/*
83 * tcp_ts_getticks() in ms, should be 1ms < x < 1000ms according to RFC 1323.
84 * We always use 1ms granularity independent of hz.
85 */
86static __inline uint32_t
87tcp_ts_getticks(void)
88{
89 struct timeval tv;
90
91 /*
92 * getmicrouptime() should be good enough for any 1-1000ms granularity.
93 * Do not use getmicrotime() here as it might break nfsroot/tcp.
94 */
95 getmicrouptime(&tv);
96 return (tv.tv_sec * 1000 + tv.tv_usec / 1000);
97}
98#endif /* _KERNEL */
99
100#endif /* _NETINET_TCP_SEQ_H_ */