c94c54e4df
A complete rationale and discussion is given in this message and the resulting discussion: http://docs.freebsd.org/cgi/mid.cgi?4177C8AD.6060706 Note that this commit removes only the functional part of T/TCP from the tcp_* related functions in the kernel. Other features introduced with RFC1644 are left intact (socket layer changes, sendmsg(2) on connection oriented protocols) and are meant to be reused by a simpler and less intrusive reimplemention of the previous T/TCP functionality. Discussed on: -arch
165 lines
5.7 KiB
C
165 lines
5.7 KiB
C
/*
|
|
* Copyright (c) 1982, 1986, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)tcp.h 8.1 (Berkeley) 6/10/93
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _NETINET_TCP_H_
|
|
#define _NETINET_TCP_H_
|
|
|
|
#include <sys/cdefs.h>
|
|
|
|
#if __BSD_VISIBLE
|
|
|
|
typedef u_int32_t tcp_seq;
|
|
|
|
#define tcp6_seq tcp_seq /* for KAME src sync over BSD*'s */
|
|
#define tcp6hdr tcphdr /* for KAME src sync over BSD*'s */
|
|
|
|
/*
|
|
* TCP header.
|
|
* Per RFC 793, September, 1981.
|
|
*/
|
|
struct tcphdr {
|
|
u_short th_sport; /* source port */
|
|
u_short th_dport; /* destination port */
|
|
tcp_seq th_seq; /* sequence number */
|
|
tcp_seq th_ack; /* acknowledgement number */
|
|
#if BYTE_ORDER == LITTLE_ENDIAN
|
|
u_int th_x2:4, /* (unused) */
|
|
th_off:4; /* data offset */
|
|
#endif
|
|
#if BYTE_ORDER == BIG_ENDIAN
|
|
u_int th_off:4, /* data offset */
|
|
th_x2:4; /* (unused) */
|
|
#endif
|
|
u_char th_flags;
|
|
#define TH_FIN 0x01
|
|
#define TH_SYN 0x02
|
|
#define TH_RST 0x04
|
|
#define TH_PUSH 0x08
|
|
#define TH_ACK 0x10
|
|
#define TH_URG 0x20
|
|
#define TH_ECE 0x40
|
|
#define TH_CWR 0x80
|
|
#define TH_FLAGS (TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG|TH_ECE|TH_CWR)
|
|
|
|
u_short th_win; /* window */
|
|
u_short th_sum; /* checksum */
|
|
u_short th_urp; /* urgent pointer */
|
|
};
|
|
|
|
#define TCPOPT_EOL 0
|
|
#define TCPOPT_NOP 1
|
|
#define TCPOPT_MAXSEG 2
|
|
#define TCPOLEN_MAXSEG 4
|
|
#define TCPOPT_WINDOW 3
|
|
#define TCPOLEN_WINDOW 3
|
|
#define TCPOPT_SACK_PERMITTED 4 /* Experimental */
|
|
#define TCPOLEN_SACK_PERMITTED 2
|
|
#define TCPOPT_SACK 5 /* Experimental */
|
|
#define TCPOLEN_SACK 8 /* 2*sizeof(tcp_seq) */
|
|
#define TCPOPT_TIMESTAMP 8
|
|
#define TCPOLEN_TIMESTAMP 10
|
|
#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
|
|
#define TCPOPT_TSTAMP_HDR \
|
|
(TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
|
|
|
|
#define MAX_TCPOPTLEN 40 /* Absolute maximum TCP options len */
|
|
|
|
#define TCPOPT_SIGNATURE 19 /* Keyed MD5: RFC 2385 */
|
|
#define TCPOLEN_SIGNATURE 18
|
|
|
|
/* Option definitions */
|
|
#define TCPOPT_SACK_PERMIT_HDR \
|
|
(TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_SACK_PERMITTED<<8|TCPOLEN_SACK_PERMITTED)
|
|
#define TCPOPT_SACK_HDR (TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_SACK<<8)
|
|
/* Miscellaneous constants */
|
|
#define MAX_SACK_BLKS 6 /* Max # SACK blocks stored at sender side */
|
|
#define TCP_MAX_SACK 3 /* MAX # SACKs sent in any segment */
|
|
|
|
|
|
/*
|
|
* Default maximum segment size for TCP.
|
|
* With an IP MTU of 576, this is 536,
|
|
* but 512 is probably more convenient.
|
|
* This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
|
|
*/
|
|
#define TCP_MSS 512
|
|
/*
|
|
* TCP_MINMSS is defined to be 216 which is fine for the smallest
|
|
* link MTU (256 bytes, AX.25 packet radio) in the Internet.
|
|
* However it is very unlikely to come across such low MTU interfaces
|
|
* these days (anno dato 2003).
|
|
* See tcp_subr.c tcp_minmss SYSCTL declaration for more comments.
|
|
* Setting this to "0" disables the minmss check.
|
|
*/
|
|
#define TCP_MINMSS 216
|
|
/*
|
|
* TCP_MINMSSOVERLOAD is defined to be 1000 which should cover any type
|
|
* of interactive TCP session.
|
|
* See tcp_subr.c tcp_minmssoverload SYSCTL declaration and tcp_input.c
|
|
* for more comments.
|
|
* Setting this to "0" disables the minmssoverload check.
|
|
*/
|
|
#define TCP_MINMSSOVERLOAD 0 /* XXX: Disabled until refined */
|
|
|
|
/*
|
|
* Default maximum segment size for TCP6.
|
|
* With an IP6 MSS of 1280, this is 1220,
|
|
* but 1024 is probably more convenient. (xxx kazu in doubt)
|
|
* This should be defined as MIN(1024, IP6_MSS - sizeof (struct tcpip6hdr))
|
|
*/
|
|
#define TCP6_MSS 1024
|
|
|
|
#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
|
|
#define TTCP_CLIENT_SND_WND 4096 /* dflt send window for T/TCP client */
|
|
|
|
#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
|
|
|
|
#define TCP_MAXBURST 4 /* maximum segments in a burst */
|
|
|
|
#define TCP_MAXHLEN (0xf<<2) /* max length of header in bytes */
|
|
#define TCP_MAXOLEN (TCP_MAXHLEN - sizeof(struct tcphdr))
|
|
/* max space left for options */
|
|
#endif /* __BSD_VISIBLE */
|
|
|
|
/*
|
|
* User-settable options (used with setsockopt).
|
|
*/
|
|
#define TCP_NODELAY 0x01 /* don't delay send to coalesce packets */
|
|
#if __BSD_VISIBLE
|
|
#define TCP_MAXSEG 0x02 /* set maximum segment size */
|
|
#define TCP_NOPUSH 0x04 /* don't push last block of write */
|
|
#define TCP_NOOPT 0x08 /* don't use TCP options */
|
|
#define TCP_MD5SIG 0x10 /* use MD5 digests (RFC2385) */
|
|
#endif
|
|
|
|
#endif /* !_NETINET_TCP_H_ */
|