| 1 | /* $Id: tcp_subr.c 63668 2016-08-31 01:34:59Z vboxsync $ */
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| 2 | /** @file
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| 3 | * NAT - TCP support.
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| 4 | */
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| 5 |
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| 6 | /*
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| 7 | * Copyright (C) 2006-2016 Oracle Corporation
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| 8 | *
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| 9 | * This file is part of VirtualBox Open Source Edition (OSE), as
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| 10 | * available from http://www.virtualbox.org. This file is free software;
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| 11 | * you can redistribute it and/or modify it under the terms of the GNU
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| 12 | * General Public License (GPL) as published by the Free Software
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| 13 | * Foundation, in version 2 as it comes in the "COPYING" file of the
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| 14 | * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
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| 15 | * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
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| 16 | */
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| 17 |
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| 18 | /*
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| 19 | * This code is based on:
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| 20 | *
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| 21 | * Copyright (c) 1982, 1986, 1988, 1990, 1993
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| 22 | * The Regents of the University of California. All rights reserved.
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| 23 | *
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| 24 | * Redistribution and use in source and binary forms, with or without
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| 25 | * modification, are permitted provided that the following conditions
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| 26 | * are met:
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| 27 | * 1. Redistributions of source code must retain the above copyright
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| 28 | * notice, this list of conditions and the following disclaimer.
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| 29 | * 2. Redistributions in binary form must reproduce the above copyright
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| 30 | * notice, this list of conditions and the following disclaimer in the
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| 31 | * documentation and/or other materials provided with the distribution.
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| 32 | * 3. All advertising materials mentioning features or use of this software
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| 33 | * must display the following acknowledgement:
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| 34 | * This product includes software developed by the University of
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| 35 | * California, Berkeley and its contributors.
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| 36 | * 4. Neither the name of the University nor the names of its contributors
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| 37 | * may be used to endorse or promote products derived from this software
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| 38 | * without specific prior written permission.
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| 39 | *
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| 40 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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| 41 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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| 42 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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| 43 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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| 44 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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| 45 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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| 46 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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| 47 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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| 48 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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| 49 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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| 50 | * SUCH DAMAGE.
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| 51 | *
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| 52 | * @(#)tcp_subr.c 8.1 (Berkeley) 6/10/93
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| 53 | * tcp_subr.c,v 1.5 1994/10/08 22:39:58 phk Exp
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| 54 | */
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| 55 |
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| 56 | /*
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| 57 | * Changes and additions relating to SLiRP
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| 58 | * Copyright (c) 1995 Danny Gasparovski.
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| 59 | *
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| 60 | * Please read the file COPYRIGHT for the
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| 61 | * terms and conditions of the copyright.
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| 62 | */
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| 63 |
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| 64 | #include <slirp.h>
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| 65 |
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| 66 |
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| 67 | /*
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| 68 | * Tcp initialization
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| 69 | */
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| 70 | void
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| 71 | tcp_init(PNATState pData)
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| 72 | {
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| 73 | tcp_iss = 1; /* wrong */
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| 74 | tcb.so_next = tcb.so_prev = &tcb;
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| 75 | tcp_last_so = &tcb;
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| 76 | tcp_reass_maxqlen = 48;
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| 77 | tcp_reass_maxseg = 256;
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| 78 | }
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| 79 |
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| 80 | /*
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| 81 | * Create template to be used to send tcp packets on a connection.
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| 82 | * Call after host entry created, fills
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| 83 | * in a skeletal tcp/ip header, minimizing the amount of work
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| 84 | * necessary when the connection is used.
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| 85 | */
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| 86 | /* struct tcpiphdr * */
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| 87 | void
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| 88 | tcp_template(struct tcpcb *tp)
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| 89 | {
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| 90 | struct socket *so = tp->t_socket;
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| 91 | register struct tcpiphdr *n = &tp->t_template;
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| 92 |
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| 93 | memset(n->ti_x1, 0, 9);
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| 94 | n->ti_pr = IPPROTO_TCP;
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| 95 | n->ti_len = RT_H2N_U16(sizeof (struct tcpiphdr) - sizeof (struct ip));
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| 96 | n->ti_src = so->so_faddr;
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| 97 | n->ti_dst = so->so_laddr;
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| 98 | n->ti_sport = so->so_fport;
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| 99 | n->ti_dport = so->so_lport;
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| 100 |
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| 101 | n->ti_seq = 0;
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| 102 | n->ti_ack = 0;
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| 103 | n->ti_x2 = 0;
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| 104 | n->ti_off = 5;
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| 105 | n->ti_flags = 0;
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| 106 | n->ti_win = 0;
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| 107 | n->ti_sum = 0;
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| 108 | n->ti_urp = 0;
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| 109 | }
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| 110 |
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| 111 | /*
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| 112 | * Send a single message to the TCP at address specified by
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| 113 | * the given TCP/IP header. If m == 0, then we make a copy
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| 114 | * of the tcpiphdr at ti and send directly to the addressed host.
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| 115 | * This is used to force keep alive messages out using the TCP
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| 116 | * template for a connection tp->t_template. If flags are given
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| 117 | * then we send a message back to the TCP which originated the
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| 118 | * segment ti, and discard the mbuf containing it and any other
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| 119 | * attached mbufs.
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| 120 | *
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| 121 | * In any case the ack and sequence number of the transmitted
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| 122 | * segment are as specified by the parameters.
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| 123 | */
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| 124 | void
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| 125 | tcp_respond(PNATState pData, struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m, tcp_seq ack, tcp_seq seq, int flags)
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| 126 | {
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| 127 | register int tlen;
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| 128 |
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| 129 | LogFlowFunc(("ENTER: tp = %R[tcpcb793], ti = %p, m = %p, ack = %u, seq = %u, flags = %x\n", tp, ti, m, ack, seq, flags));
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| 130 |
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| 131 | if (m == 0)
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| 132 | {
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| 133 | if ((m = m_gethdr(pData, M_DONTWAIT, MT_HEADER)) == NULL)
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| 134 | return;
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| 135 | #ifdef TCP_COMPAT_42
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| 136 | tlen = 1;
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| 137 | #else
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| 138 | tlen = 0;
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| 139 | #endif
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| 140 | m->m_data += if_maxlinkhdr;
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| 141 | m->m_pkthdr.header = mtod(m, void *);
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| 142 | *mtod(m, struct tcpiphdr *) = *ti;
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| 143 | ti = mtod(m, struct tcpiphdr *);
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| 144 | flags = TH_ACK;
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| 145 | }
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| 146 | else
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| 147 | {
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| 148 | /*
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| 149 | * ti points into m so the next line is just making
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| 150 | * the mbuf point to ti
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| 151 | */
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| 152 | m->m_data = (caddr_t)ti;
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| 153 |
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| 154 | m->m_len = sizeof (struct tcpiphdr);
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| 155 | tlen = 0;
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| 156 | #define xchg(a,b,type) { type t; t = a; a = b; b = t; }
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| 157 | xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, u_int32_t);
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| 158 | xchg(ti->ti_dport, ti->ti_sport, u_int16_t);
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| 159 | #undef xchg
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| 160 | }
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| 161 | ti->ti_len = RT_H2N_U16((u_short)(sizeof (struct tcphdr) + tlen));
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| 162 | tlen += sizeof (struct tcpiphdr);
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| 163 | m->m_len = tlen;
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| 164 |
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| 165 | memset(ti->ti_x1, 0, 9);
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| 166 | ti->ti_seq = RT_H2N_U32(seq);
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| 167 | ti->ti_ack = RT_H2N_U32(ack);
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| 168 | ti->ti_x2 = 0;
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| 169 | ti->ti_off = sizeof (struct tcphdr) >> 2;
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| 170 | ti->ti_flags = flags;
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| 171 | if (tp)
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| 172 | {
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| 173 | int win = sbspace(&tp->t_socket->so_rcv);
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| 174 | ti->ti_win = RT_H2N_U16((u_int16_t) (win >> tp->rcv_scale));
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| 175 | }
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| 176 | else
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| 177 | ti->ti_win = 0;
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| 178 | ti->ti_urp = 0;
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| 179 | ti->ti_sum = 0;
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| 180 | ti->ti_sum = cksum(m, tlen);
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| 181 | ((struct ip *)ti)->ip_len = tlen;
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| 182 |
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| 183 | if(flags & TH_RST)
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| 184 | ((struct ip *)ti)->ip_ttl = MAXTTL;
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| 185 | else
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| 186 | ((struct ip *)ti)->ip_ttl = ip_defttl;
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| 187 |
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| 188 | (void) ip_output(pData, (struct socket *)0, m);
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| 189 | }
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| 190 |
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| 191 | /*
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| 192 | * Create a new TCP control block, making an
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| 193 | * empty reassembly queue and hooking it to the argument
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| 194 | * protocol control block.
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| 195 | */
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| 196 | struct tcpcb *
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| 197 | tcp_newtcpcb(PNATState pData, struct socket *so)
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| 198 | {
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| 199 | register struct tcpcb *tp;
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| 200 |
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| 201 | tp = (struct tcpcb *)RTMemAllocZ(sizeof(*tp));
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| 202 | if (tp == NULL)
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| 203 | return ((struct tcpcb *)0);
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| 204 |
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| 205 | tp->t_maxseg = tcp_mssdflt;
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| 206 |
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| 207 | tp->t_flags = tcp_do_rfc1323 ? (TF_REQ_SCALE|TF_REQ_TSTMP) : 0;
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| 208 | tp->t_socket = so;
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| 209 |
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| 210 | /*
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| 211 | * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
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| 212 | * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives
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| 213 | * reasonable initial retransmit time.
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| 214 | */
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| 215 | tp->t_srtt = TCPTV_SRTTBASE;
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| 216 | tp->t_rttvar = tcp_rttdflt * PR_SLOWHZ << 2;
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| 217 | tp->t_rttmin = TCPTV_MIN;
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| 218 |
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| 219 | TCPT_RANGESET(tp->t_rxtcur,
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| 220 | ((TCPTV_SRTTBASE >> 2) + (TCPTV_SRTTDFLT << 2)) >> 1,
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| 221 | TCPTV_MIN, TCPTV_REXMTMAX);
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| 222 |
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| 223 | tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
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| 224 | tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
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| 225 | TCP_STATE_SWITCH_TO(tp, TCPS_CLOSED);
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| 226 |
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| 227 | so->so_tcpcb = tp;
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| 228 | so->so_type = IPPROTO_TCP;
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| 229 |
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| 230 | return (tp);
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| 231 | }
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| 232 |
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| 233 | /*
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| 234 | * Drop a TCP connection, reporting
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| 235 | * the specified error. If connection is synchronized,
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| 236 | * then send a RST to peer.
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| 237 | */
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| 238 | struct tcpcb *tcp_drop(PNATState pData, struct tcpcb *tp, int err)
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| 239 | {
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| 240 | /* tcp_drop(tp, errno)
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| 241 | register struct tcpcb *tp;
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| 242 | int errno;
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| 243 | {
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| 244 | */
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| 245 | int fUninitializedTemplate = 0;
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| 246 | #ifndef LOG_ENABLED
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| 247 | NOREF(err);
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| 248 | #endif
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| 249 | LogFlowFunc(("ENTER: tp = %R[tcpcb793], errno = %d\n", tp, err));
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| 250 | fUninitializedTemplate = RT_BOOL(( tp
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| 251 | && ( tp->t_template.ti_src.s_addr == INADDR_ANY
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| 252 | || tp->t_template.ti_dst.s_addr == INADDR_ANY)));
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| 253 |
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| 254 | if ( TCPS_HAVERCVDSYN(tp->t_state)
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| 255 | && !fUninitializedTemplate)
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| 256 | {
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| 257 | TCP_STATE_SWITCH_TO(tp, TCPS_CLOSED);
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| 258 | (void) tcp_output(pData, tp);
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| 259 | tcpstat.tcps_drops++;
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| 260 | }
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| 261 | else
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| 262 | tcpstat.tcps_conndrops++;
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| 263 | #if 0
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| 264 | if (errno == ETIMEDOUT && tp->t_softerror)
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| 265 | errno = tp->t_softerror;
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| 266 |
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| 267 | so->so_error = errno;
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| 268 | #endif
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| 269 | return (tcp_close(pData, tp));
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| 270 | }
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| 271 |
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| 272 | /*
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| 273 | * Close a TCP control block:
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| 274 | * discard all space held by the tcp
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| 275 | * discard internet protocol block
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| 276 | * wake up any sleepers
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| 277 | */
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| 278 | struct tcpcb *
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| 279 | tcp_close(PNATState pData, register struct tcpcb *tp)
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| 280 | {
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| 281 | struct socket *so = tp->t_socket;
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| 282 |
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| 283 | struct tseg_qent *te = NULL;
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| 284 | LogFlowFunc(("ENTER: tp = %R[tcpcb793]\n", tp));
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| 285 | /*XXX: freeing the reassembly queue */
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| 286 | while (!LIST_EMPTY(&tp->t_segq))
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| 287 | {
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| 288 | te = LIST_FIRST(&tp->t_segq);
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| 289 | LIST_REMOVE(te, tqe_q);
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| 290 | m_freem(pData, te->tqe_m);
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| 291 | RTMemFree(te);
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| 292 | tcp_reass_qsize--;
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| 293 | }
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| 294 | RTMemFree(tp);
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| 295 | so->so_tcpcb = 0;
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| 296 | soisfdisconnected(so);
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| 297 | /* clobber input socket cache if we're closing the cached connection */
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| 298 | if (so == tcp_last_so)
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| 299 | tcp_last_so = &tcb;
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| 300 | if (so->s != -1)
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| 301 | closesocket(so->s);
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| 302 | /* Avoid double free if the socket is listening and therefore doesn't have
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| 303 | * any sbufs reserved. */
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| 304 | if (!(so->so_state & SS_FACCEPTCONN))
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| 305 | {
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| 306 | sbfree(&so->so_rcv);
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| 307 | sbfree(&so->so_snd);
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| 308 | }
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| 309 | sofree(pData, so);
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| 310 | SOCKET_UNLOCK(so);
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| 311 | tcpstat.tcps_closed++;
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| 312 | return ((struct tcpcb *)0);
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| 313 | }
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| 314 |
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| 315 | void
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| 316 | tcp_drain(void)
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| 317 | {
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| 318 | /* XXX */
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| 319 | }
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| 320 |
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| 321 | /*
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| 322 | * When a source quench is received, close congestion window
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| 323 | * to one segment. We will gradually open it again as we proceed.
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| 324 | */
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| 325 |
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| 326 | #if 0
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| 327 |
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| 328 | void
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| 329 | tcp_quench(i, int errno)
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| 330 | {
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| 331 | struct tcpcb *tp = intotcpcb(inp);
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| 332 |
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| 333 | if (tp)
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| 334 | tp->snd_cwnd = tp->t_maxseg;
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| 335 | }
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| 336 |
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| 337 | #endif
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| 338 |
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| 339 | /*
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| 340 | * TCP protocol interface to socket abstraction.
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| 341 | */
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| 342 |
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| 343 | /*
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| 344 | * User issued close, and wish to trail through shutdown states:
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| 345 | * if never received SYN, just forget it. If got a SYN from peer,
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| 346 | * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
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| 347 | * If already got a FIN from peer, then almost done; go to LAST_ACK
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| 348 | * state. In all other cases, have already sent FIN to peer (e.g.
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| 349 | * after PRU_SHUTDOWN), and just have to play tedious game waiting
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| 350 | * for peer to send FIN or not respond to keep-alives, etc.
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| 351 | * We can let the user exit from the close as soon as the FIN is acked.
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| 352 | */
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| 353 | void
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| 354 | tcp_sockclosed(PNATState pData, struct tcpcb *tp)
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| 355 | {
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| 356 | LogFlowFunc(("ENTER: tp = %R[tcpcb793]\n", tp));
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| 357 | LogFunc(("tp->t_socket:%R[natsock]\n",tp->t_socket));
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| 358 |
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| 359 | switch (tp->t_state)
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| 360 | {
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| 361 | case TCPS_CLOSED:
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| 362 | case TCPS_LISTEN:
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| 363 | case TCPS_SYN_SENT:
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| 364 | TCP_STATE_SWITCH_TO(tp, TCPS_CLOSED);
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| 365 | tp = tcp_close(pData, tp);
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| 366 | break;
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| 367 |
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| 368 | case TCPS_SYN_RECEIVED:
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| 369 | case TCPS_ESTABLISHED:
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| 370 | TCP_STATE_SWITCH_TO(tp, TCPS_FIN_WAIT_1);
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| 371 | break;
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| 372 |
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| 373 | case TCPS_CLOSE_WAIT:
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| 374 | TCP_STATE_SWITCH_TO(tp, TCPS_LAST_ACK);
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| 375 | break;
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| 376 | }
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| 377 | /* soisfdisconnecting(tp->t_socket); */
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| 378 | if ( tp
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| 379 | && tp->t_state >= TCPS_FIN_WAIT_2)
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| 380 | soisfdisconnected(tp->t_socket);
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| 381 | /*
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| 382 | * (vasily) there're situations when the FIN or FIN,ACK are lost (Windows host)
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| 383 | * and retransmitting keeps VBox busy on sending closing sequences *very* frequent,
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| 384 | * easting a lot of CPU. To avoid this we don't sent on sockets marked as closed
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| 385 | * (see slirp.c for details about setting so_close member).
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| 386 | */
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| 387 | if ( tp
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| 388 | && tp->t_socket
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| 389 | && !tp->t_socket->so_close)
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| 390 | tcp_output(pData, tp);
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| 391 | }
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| 392 |
|
|---|
| 393 | /*
|
|---|
| 394 | * Connect to a host on the Internet
|
|---|
| 395 | * Called by tcp_input
|
|---|
| 396 | * Only do a connect, the tcp fields will be set in tcp_input
|
|---|
| 397 | * return 0 if there's a result of the connect,
|
|---|
| 398 | * else return -1 means we're still connecting
|
|---|
| 399 | * The return value is almost always -1 since the socket is
|
|---|
| 400 | * nonblocking. Connect returns after the SYN is sent, and does
|
|---|
| 401 | * not wait for ACK+SYN.
|
|---|
| 402 | */
|
|---|
| 403 | int tcp_fconnect(PNATState pData, struct socket *so)
|
|---|
| 404 | {
|
|---|
| 405 | int ret = 0;
|
|---|
| 406 |
|
|---|
| 407 | LogFlowFunc(("ENTER: so = %R[natsock]\n", so));
|
|---|
| 408 |
|
|---|
| 409 | if ((ret = so->s = socket(AF_INET, SOCK_STREAM, 0)) >= 0)
|
|---|
| 410 | {
|
|---|
| 411 | int opt, s = so->s;
|
|---|
| 412 | struct sockaddr_in addr;
|
|---|
| 413 |
|
|---|
| 414 | fd_nonblock(s);
|
|---|
| 415 | opt = 1;
|
|---|
| 416 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&opt, sizeof(opt));
|
|---|
| 417 | opt = 1;
|
|---|
| 418 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (char *)&opt, sizeof(opt));
|
|---|
| 419 |
|
|---|
| 420 | addr.sin_family = AF_INET;
|
|---|
| 421 | if ((so->so_faddr.s_addr & RT_H2N_U32(pData->netmask)) == pData->special_addr.s_addr)
|
|---|
| 422 | {
|
|---|
| 423 | /* It's an alias */
|
|---|
| 424 | switch(RT_N2H_U32(so->so_faddr.s_addr) & ~pData->netmask)
|
|---|
| 425 | {
|
|---|
| 426 | case CTL_DNS:
|
|---|
| 427 | /*
|
|---|
| 428 | * TCP DNS proxy. We only support "forwarding" to
|
|---|
| 429 | * single server. We don't have infrastructure in
|
|---|
| 430 | * place to re-try connections to other servers.
|
|---|
| 431 | */
|
|---|
| 432 | if ( pData->fUseDnsProxy
|
|---|
| 433 | && so->so_fport == RT_H2N_U16_C(53))
|
|---|
| 434 | {
|
|---|
| 435 | struct dns_entry *ns = TAILQ_LAST(&pData->pDnsList, dns_list_head);
|
|---|
| 436 | if (ns != NULL)
|
|---|
| 437 | {
|
|---|
| 438 | addr.sin_addr = ns->de_addr;
|
|---|
| 439 | break;
|
|---|
| 440 | }
|
|---|
| 441 | }
|
|---|
| 442 | /* FALLTHROUGH */
|
|---|
| 443 | case CTL_ALIAS:
|
|---|
| 444 | default:
|
|---|
| 445 | addr.sin_addr = loopback_addr;
|
|---|
| 446 | break;
|
|---|
| 447 | }
|
|---|
| 448 | }
|
|---|
| 449 | else
|
|---|
| 450 | addr.sin_addr = so->so_faddr;
|
|---|
| 451 | addr.sin_port = so->so_fport;
|
|---|
| 452 |
|
|---|
| 453 | Log2((" connect()ing, addr.sin_port=%d, addr.sin_addr.s_addr=%.16s\n",
|
|---|
| 454 | RT_N2H_U16(addr.sin_port), inet_ntoa(addr.sin_addr)));
|
|---|
| 455 | /* We don't care what port we get */
|
|---|
| 456 | ret = connect(s,(struct sockaddr *)&addr,sizeof (addr));
|
|---|
| 457 |
|
|---|
| 458 | /*
|
|---|
| 459 | * If it's not in progress, it failed, so we just return 0,
|
|---|
| 460 | * without clearing SS_NOFDREF
|
|---|
| 461 | */
|
|---|
| 462 | soisfconnecting(so);
|
|---|
| 463 | }
|
|---|
| 464 |
|
|---|
| 465 | return(ret);
|
|---|
| 466 | }
|
|---|
| 467 |
|
|---|
| 468 | /*
|
|---|
| 469 | * Accept the socket and connect to the local-host
|
|---|
| 470 | *
|
|---|
| 471 | * We have a problem. The correct thing to do would be
|
|---|
| 472 | * to first connect to the local-host, and only if the
|
|---|
| 473 | * connection is accepted, then do an accept() here.
|
|---|
| 474 | * But, a) we need to know who's trying to connect
|
|---|
| 475 | * to the socket to be able to SYN the local-host, and
|
|---|
| 476 | * b) we are already connected to the foreign host by
|
|---|
| 477 | * the time it gets to accept(), so... We simply accept
|
|---|
| 478 | * here and SYN the local-host.
|
|---|
| 479 | */
|
|---|
| 480 | void
|
|---|
| 481 | tcp_connect(PNATState pData, struct socket *inso)
|
|---|
| 482 | {
|
|---|
| 483 | struct socket *so;
|
|---|
| 484 | struct sockaddr_in addr;
|
|---|
| 485 | socklen_t addrlen = sizeof(struct sockaddr_in);
|
|---|
| 486 | struct tcpcb *tp;
|
|---|
| 487 | int s, opt;
|
|---|
| 488 | int status;
|
|---|
| 489 | socklen_t optlen;
|
|---|
| 490 | static int cVerbose = 1;
|
|---|
| 491 |
|
|---|
| 492 | LogFlowFunc(("ENTER: inso = %R[natsock]\n", inso));
|
|---|
| 493 |
|
|---|
| 494 | if ( inso->so_laddr.s_addr == INADDR_ANY /* delayed port-forwarding? */
|
|---|
| 495 | && pData->guest_addr_guess.s_addr == INADDR_ANY)
|
|---|
| 496 | {
|
|---|
| 497 | LogRel2(("NAT: Port-forward: guest address unknown for %R[natsock]\n", inso));
|
|---|
| 498 | closesocket(accept(inso->s, NULL, NULL));
|
|---|
| 499 | if (inso->so_state & SS_FACCEPTONCE)
|
|---|
| 500 | tcp_close(pData, sototcpcb(inso));
|
|---|
| 501 | return;
|
|---|
| 502 | }
|
|---|
| 503 |
|
|---|
| 504 | /*
|
|---|
| 505 | * If it's an SS_ACCEPTONCE socket, no need to socreate()
|
|---|
| 506 | * another socket, just use the accept() socket.
|
|---|
| 507 | */
|
|---|
| 508 | if (inso->so_state & SS_FACCEPTONCE)
|
|---|
| 509 | {
|
|---|
| 510 | /* FACCEPTONCE already have a tcpcb */
|
|---|
| 511 | so = inso;
|
|---|
| 512 | }
|
|---|
| 513 | else
|
|---|
| 514 | {
|
|---|
| 515 | if ((so = socreate()) == NULL)
|
|---|
| 516 | {
|
|---|
| 517 | /* If it failed, get rid of the pending connection */
|
|---|
| 518 | closesocket(accept(inso->s,(struct sockaddr *)&addr,&addrlen));
|
|---|
| 519 | return;
|
|---|
| 520 | }
|
|---|
| 521 | if (tcp_attach(pData, so) < 0)
|
|---|
| 522 | {
|
|---|
| 523 | RTMemFree(so); /* NOT sofree */
|
|---|
| 524 | return;
|
|---|
| 525 | }
|
|---|
| 526 | so->so_laddr = inso->so_laddr;
|
|---|
| 527 | so->so_lport = inso->so_lport;
|
|---|
| 528 | }
|
|---|
| 529 |
|
|---|
| 530 | if (so->so_laddr.s_addr == INADDR_ANY)
|
|---|
| 531 | {
|
|---|
| 532 | LogRel2(("NAT: Port-forward: using %RTnaipv4 for %R[natsock]\n",
|
|---|
| 533 | pData->guest_addr_guess.s_addr, inso));
|
|---|
| 534 | so->so_laddr = pData->guest_addr_guess;
|
|---|
| 535 | }
|
|---|
| 536 |
|
|---|
| 537 | (void) tcp_mss(pData, sototcpcb(so), 0);
|
|---|
| 538 |
|
|---|
| 539 | fd_nonblock(inso->s);
|
|---|
| 540 | if ((s = accept(inso->s,(struct sockaddr *)&addr,&addrlen)) < 0)
|
|---|
| 541 | {
|
|---|
| 542 | tcp_close(pData, sototcpcb(so)); /* This will sofree() as well */
|
|---|
| 543 | return;
|
|---|
| 544 | }
|
|---|
| 545 | fd_nonblock(s);
|
|---|
| 546 | opt = 1;
|
|---|
| 547 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR,(char *)&opt, sizeof(int));
|
|---|
| 548 | opt = 1;
|
|---|
| 549 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE,(char *)&opt, sizeof(int));
|
|---|
| 550 | #if 0
|
|---|
| 551 | opt = 1;
|
|---|
| 552 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY,(char *)&opt, sizeof(int));
|
|---|
| 553 | #endif
|
|---|
| 554 |
|
|---|
| 555 | optlen = sizeof(int);
|
|---|
| 556 | status = getsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&opt, &optlen);
|
|---|
| 557 | if (status < 0)
|
|---|
| 558 | {
|
|---|
| 559 | LogRel(("NAT: Error(%d) while getting RCV capacity\n", errno));
|
|---|
| 560 | goto no_sockopt;
|
|---|
| 561 | }
|
|---|
| 562 | if (cVerbose > 0)
|
|---|
| 563 | LogRel(("NAT: Old socket recv size: %dKB\n", opt / 1024));
|
|---|
| 564 | /** @todo (r-vvl) make it configurable (via extra data) */
|
|---|
| 565 | opt = pData->socket_rcv;
|
|---|
| 566 | status = setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&opt, sizeof(int));
|
|---|
| 567 | if (status < 0)
|
|---|
| 568 | {
|
|---|
| 569 | LogRel(("NAT: Error(%d) while setting RCV capacity to (%d)\n", errno, opt));
|
|---|
| 570 | goto no_sockopt;
|
|---|
| 571 | }
|
|---|
| 572 | optlen = sizeof(int);
|
|---|
| 573 | status = getsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&opt, &optlen);
|
|---|
| 574 | if (status < 0)
|
|---|
| 575 | {
|
|---|
| 576 | LogRel(("NAT: Error(%d) while getting SND capacity\n", errno));
|
|---|
| 577 | goto no_sockopt;
|
|---|
| 578 | }
|
|---|
| 579 | if (cVerbose > 0)
|
|---|
| 580 | LogRel(("NAT: Old socket send size: %dKB\n", opt / 1024));
|
|---|
| 581 | opt = pData->socket_rcv;
|
|---|
| 582 | status = setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&opt, sizeof(int));
|
|---|
| 583 | if (status < 0)
|
|---|
| 584 | {
|
|---|
| 585 | LogRel(("NAT: Error(%d) while setting SND capacity to (%d)\n", errno, opt));
|
|---|
| 586 | goto no_sockopt;
|
|---|
| 587 | }
|
|---|
| 588 | if (cVerbose > 0)
|
|---|
| 589 | cVerbose--;
|
|---|
| 590 |
|
|---|
| 591 | no_sockopt:
|
|---|
| 592 | so->so_fport = addr.sin_port;
|
|---|
| 593 | so->so_faddr = addr.sin_addr;
|
|---|
| 594 | /* Translate connections from localhost to the real hostname */
|
|---|
| 595 | if (so->so_faddr.s_addr == 0 || so->so_faddr.s_addr == loopback_addr.s_addr)
|
|---|
| 596 | so->so_faddr = alias_addr;
|
|---|
| 597 |
|
|---|
| 598 | /* Close the accept() socket, set right state */
|
|---|
| 599 | if (inso->so_state & SS_FACCEPTONCE)
|
|---|
| 600 | {
|
|---|
| 601 | closesocket(so->s); /* If we only accept once, close the accept() socket */
|
|---|
| 602 | so->so_state = SS_NOFDREF; /* Don't select it yet, even though we have an FD */
|
|---|
| 603 | /* if it's not FACCEPTONCE, it's already NOFDREF */
|
|---|
| 604 | }
|
|---|
| 605 | so->s = s;
|
|---|
| 606 |
|
|---|
| 607 | tp = sototcpcb(so);
|
|---|
| 608 |
|
|---|
| 609 | tcp_template(tp);
|
|---|
| 610 |
|
|---|
| 611 | /* Compute window scaling to request. */
|
|---|
| 612 | /* while (tp->request_r_scale < TCP_MAX_WINSHIFT
|
|---|
| 613 | * && (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
|
|---|
| 614 | * tp->request_r_scale++;
|
|---|
| 615 | */
|
|---|
| 616 |
|
|---|
| 617 | /* soisconnecting(so); */ /* NOFDREF used instead */
|
|---|
| 618 | tcpstat.tcps_connattempt++;
|
|---|
| 619 |
|
|---|
| 620 | TCP_STATE_SWITCH_TO(tp, TCPS_SYN_SENT);
|
|---|
| 621 | tp->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT;
|
|---|
| 622 | tp->iss = tcp_iss;
|
|---|
| 623 | tcp_iss += TCP_ISSINCR/2;
|
|---|
| 624 | tcp_sendseqinit(tp);
|
|---|
| 625 | tcp_output(pData, tp);
|
|---|
| 626 | }
|
|---|
| 627 |
|
|---|
| 628 | /*
|
|---|
| 629 | * Attach a TCPCB to a socket.
|
|---|
| 630 | */
|
|---|
| 631 | int
|
|---|
| 632 | tcp_attach(PNATState pData, struct socket *so)
|
|---|
| 633 | {
|
|---|
| 634 | /* We're attaching already attached socket??? */
|
|---|
| 635 | Assert(so->so_type == 0);
|
|---|
| 636 | if ((so->so_tcpcb = tcp_newtcpcb(pData, so)) == NULL)
|
|---|
| 637 | return -1;
|
|---|
| 638 |
|
|---|
| 639 | SOCKET_LOCK_CREATE(so);
|
|---|
| 640 | QSOCKET_LOCK(tcb);
|
|---|
| 641 | insque(pData, so, &tcb);
|
|---|
| 642 | NSOCK_INC();
|
|---|
| 643 | QSOCKET_UNLOCK(tcb);
|
|---|
| 644 | return 0;
|
|---|
| 645 | }
|
|---|
