xref: /xnu-11215.81.4/bsd/netinet/tcp_seq.h (revision d4514f0bc1d3f944c22d92e68b646ac3fb40d452) !
1 /*
2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*
29  * Copyright (c) 1982, 1986, 1993, 1995
30  *	The Regents of the University of California.  All rights reserved.
31  *
32  * Redistribution and use in source and binary forms, with or without
33  * modification, are permitted provided that the following conditions
34  * are met:
35  * 1. Redistributions of source code must retain the above copyright
36  *    notice, this list of conditions and the following disclaimer.
37  * 2. Redistributions in binary form must reproduce the above copyright
38  *    notice, this list of conditions and the following disclaimer in the
39  *    documentation and/or other materials provided with the distribution.
40  * 3. All advertising materials mentioning features or use of this software
41  *    must display the following acknowledgement:
42  *	This product includes software developed by the University of
43  *	California, Berkeley and its contributors.
44  * 4. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)tcp_seq.h	8.3 (Berkeley) 6/21/95
61  * $FreeBSD: src/sys/netinet/tcp_seq.h,v 1.11.2.5 2001/08/22 00:59:12 silby Exp $
62  */
63 
64 #ifndef _NETINET_TCP_SEQ_H_
65 #define _NETINET_TCP_SEQ_H_
66 #include <sys/appleapiopts.h>
67 /*
68  * TCP sequence numbers are 32 bit integers operated
69  * on with modular arithmetic.  These macros can be
70  * used to compare such integers.
71  */
72 #define SEQ_LT(a, b)     ((int)((a)-(b)) < 0)
73 #define SEQ_LEQ(a, b)    ((int)((a)-(b)) <= 0)
74 #define SEQ_GT(a, b)     ((int)((a)-(b)) > 0)
75 #define SEQ_GEQ(a, b)    ((int)((a)-(b)) >= 0)
76 
77 #define SEQ_MIN(a, b)   ((SEQ_LT(a, b)) ? (a) : (b))
78 #define SEQ_MAX(a, b)   ((SEQ_GT(a, b)) ? (a) : (b))
79 
80 /* for modulo comparisons of timestamps */
81 #define TSTMP_LT(a, b)   ((int)((a)-(b)) < 0)
82 #define TSTMP_GT(a, b)   ((int)((a)-(b)) > 0)
83 #define TSTMP_LEQ(a, b)  ((int)((a)-(b)) <= 0)
84 #define TSTMP_GEQ(a, b)  ((int)((a)-(b)) >= 0)
85 
86 /*
87  * TCP connection counts are 32 bit integers operated
88  * on with modular arithmetic.  These macros can be
89  * used to compare such integers.
90  */
91 #define CC_LT(a, b)      ((int)((a)-(b)) < 0)
92 #define CC_LEQ(a, b)     ((int)((a)-(b)) <= 0)
93 #define CC_GT(a, b)      ((int)((a)-(b)) > 0)
94 #define CC_GEQ(a, b)     ((int)((a)-(b)) >= 0)
95 
96 /* Macro to increment a CC: skip 0 which has a special meaning */
97 #define CC_INC(c)       (++(c) == 0 ? ++(c) : (c))
98 
99 #ifdef KERNEL_PRIVATE
100 /*
101  * Macros to initialize tcp sequence numbers for
102  * send and receive from initial send and receive
103  * sequence numbers.
104  */
105 #define tcp_rcvseqinit(tp) \
106 	(tp)->rcv_adv = (tp)->rcv_nxt = (tp)->rcv_high = (tp)->irs + 1
107 
108 #define tcp_sendseqinit(tp) \
109 	(tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \
110 	(tp)->snd_recover = (tp)->iss
111 
112 #define TCP_PAWS_IDLE   (24 * 24 * 60 * 60 * TCP_RETRANSHZ)
113 /* timestamp wrap-around time */
114 #endif /* KERNEL_PRIVATE */
115 #endif /* _NETINET_TCP_SEQ_H_ */
116