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* Copyright (c) 1982, 1986, 1993
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* The Regents of the University of California. All rights reserved.
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* @(#)tcp.h 8.1 (Berkeley) 6/10/93
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* tcp.h,v 1.3 1994/08/21 05:27:34 paul Exp
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typedef u_int32_t tcp_seq;
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#define PR_SLOWHZ 2 /* 2 slow timeouts per second (approx) */
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#define PR_FASTHZ 5 /* 5 fast timeouts per second (not important) */
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extern int tcp_rcvspace;
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extern int tcp_sndspace;
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extern struct socket *tcp_last_so;
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#define TCP_SNDSPACE 8192
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#define TCP_RCVSPACE 8192
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* Per RFC 793, September, 1981.
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u_int16_t th_sport; /* source port */
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u_int16_t th_dport; /* destination port */
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tcp_seq th_seq; /* sequence number */
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tcp_seq th_ack; /* acknowledgement number */
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#ifdef WORDS_BIGENDIAN
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u_int th_off:4, /* data offset */
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th_x2:4; /* (unused) */
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u_int th_x2:4, /* (unused) */
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th_off:4; /* data offset */
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u_int16_t th_win; /* window */
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u_int16_t th_sum; /* checksum */
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u_int16_t th_urp; /* urgent pointer */
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#define TCPOPT_MAXSEG 2
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#define TCPOLEN_MAXSEG 4
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#define TCPOPT_WINDOW 3
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#define TCPOLEN_WINDOW 3
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#define TCPOPT_SACK_PERMITTED 4 /* Experimental */
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#define TCPOLEN_SACK_PERMITTED 2
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#define TCPOPT_SACK 5 /* Experimental */
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#define TCPOPT_TIMESTAMP 8
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#define TCPOLEN_TIMESTAMP 10
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#define TCPOLEN_TSTAMP_APPA (TCPOLEN_TIMESTAMP+2) /* appendix A */
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#define TCPOPT_TSTAMP_HDR \
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(TCPOPT_NOP<<24|TCPOPT_NOP<<16|TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)
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* Default maximum segment size for TCP.
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* With an IP MSS of 576, this is 536,
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* but 512 is probably more convenient.
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* This should be defined as MIN(512, IP_MSS - sizeof (struct tcpiphdr)).
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#define TCP_MAXWIN 65535 /* largest value for (unscaled) window */
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#define TCP_MAX_WINSHIFT 14 /* maximum window shift */
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* User-settable options (used with setsockopt).
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/* #define TCP_NODELAY 0x01 */ /* don't delay send to coalesce packets */
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/* #define TCP_MAXSEG 0x02 */ /* set maximum segment size */
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* TCP FSM state definitions.
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* Per RFC793, September, 1981.
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#define TCP_NSTATES 11
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#define TCPS_CLOSED 0 /* closed */
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#define TCPS_LISTEN 1 /* listening for connection */
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#define TCPS_SYN_SENT 2 /* active, have sent syn */
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#define TCPS_SYN_RECEIVED 3 /* have send and received syn */
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/* states < TCPS_ESTABLISHED are those where connections not established */
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#define TCPS_ESTABLISHED 4 /* established */
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#define TCPS_CLOSE_WAIT 5 /* rcvd fin, waiting for close */
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/* states > TCPS_CLOSE_WAIT are those where user has closed */
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#define TCPS_FIN_WAIT_1 6 /* have closed, sent fin */
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#define TCPS_CLOSING 7 /* closed xchd FIN; await FIN ACK */
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#define TCPS_LAST_ACK 8 /* had fin and close; await FIN ACK */
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/* states > TCPS_CLOSE_WAIT && < TCPS_FIN_WAIT_2 await ACK of FIN */
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#define TCPS_FIN_WAIT_2 9 /* have closed, fin is acked */
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#define TCPS_TIME_WAIT 10 /* in 2*msl quiet wait after close */
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#define TCPS_HAVERCVDSYN(s) ((s) >= TCPS_SYN_RECEIVED)
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#define TCPS_HAVEESTABLISHED(s) ((s) >= TCPS_ESTABLISHED)
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#define TCPS_HAVERCVDFIN(s) ((s) >= TCPS_TIME_WAIT)
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* TCP sequence numbers are 32 bit integers operated
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* on with modular arithmetic. These macros can be
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* used to compare such integers.
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#define SEQ_LT(a,b) ((int)((a)-(b)) < 0)
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#define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0)
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#define SEQ_GT(a,b) ((int)((a)-(b)) > 0)
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#define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0)
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* Macros to initialize tcp sequence numbers for
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* send and receive from initial send and receive
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#define tcp_rcvseqinit(tp) \
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(tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1
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#define tcp_sendseqinit(tp) \
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(tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = (tp)->iss
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#define TCP_ISSINCR (125*1024) /* increment for tcp_iss each second */
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extern tcp_seq tcp_iss; /* tcp initial send seq # */
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extern char *tcpstates[];