1 | /* $Id: tcp_subr.c 93115 2022-01-01 11:31:46Z 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) 2006-2022 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 |
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393 | /*
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394 | * Connect to a host on the Internet
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395 | * Called by tcp_input
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396 | * Only do a connect, the tcp fields will be set in tcp_input
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397 | * return 0 if there's a result of the connect,
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398 | * else return -1 means we're still connecting
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399 | * The return value is almost always -1 since the socket is
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400 | * nonblocking. Connect returns after the SYN is sent, and does
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401 | * not wait for ACK+SYN.
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402 | */
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403 | int tcp_fconnect(PNATState pData, struct socket *so)
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404 | {
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405 | int ret = 0;
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406 |
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407 | LogFlowFunc(("ENTER: so = %R[natsock]\n", so));
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408 |
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409 | if ((ret = so->s = socket(AF_INET, SOCK_STREAM, 0)) >= 0)
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410 | {
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411 | int opt, s = so->s;
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412 | struct sockaddr_in addr;
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413 |
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414 | fd_nonblock(s);
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415 |
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416 | opt = 1;
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417 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (char *)&opt, sizeof(opt));
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418 | opt = 1;
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419 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (char *)&opt, sizeof(opt));
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420 |
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421 | ret = sobind(pData, so);
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422 | if (ret != 0)
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423 | return ret;
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424 |
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425 | addr.sin_family = AF_INET;
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426 | if ((so->so_faddr.s_addr & RT_H2N_U32(pData->netmask)) == pData->special_addr.s_addr)
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427 | {
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428 | /* It's an alias */
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429 | switch(RT_N2H_U32(so->so_faddr.s_addr) & ~pData->netmask)
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430 | {
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431 | case CTL_DNS:
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432 | /*
|
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433 | * TCP DNS proxy. We only support "forwarding" to
|
---|
434 | * single server. We don't have infrastructure in
|
---|
435 | * place to re-try connections to other servers.
|
---|
436 | */
|
---|
437 | if ( pData->fUseDnsProxy
|
---|
438 | && so->so_fport == RT_H2N_U16_C(53))
|
---|
439 | {
|
---|
440 | struct dns_entry *ns = TAILQ_LAST(&pData->pDnsList, dns_list_head);
|
---|
441 | if (ns != NULL)
|
---|
442 | {
|
---|
443 | addr.sin_addr = ns->de_addr;
|
---|
444 | break;
|
---|
445 | }
|
---|
446 | }
|
---|
447 | RT_FALL_THRU();
|
---|
448 | case CTL_ALIAS:
|
---|
449 | default:
|
---|
450 | addr.sin_addr = loopback_addr;
|
---|
451 | break;
|
---|
452 | }
|
---|
453 | }
|
---|
454 | else
|
---|
455 | addr.sin_addr = so->so_faddr;
|
---|
456 | addr.sin_port = so->so_fport;
|
---|
457 |
|
---|
458 | Log2(("NAT: tcp connect to %RTnaipv4:%d\n",
|
---|
459 | addr.sin_addr.s_addr, RT_N2H_U16(addr.sin_port)));
|
---|
460 |
|
---|
461 | ret = connect(s,(struct sockaddr *)&addr,sizeof (addr));
|
---|
462 |
|
---|
463 | /*
|
---|
464 | * If it's not in progress, it failed, so we just return 0,
|
---|
465 | * without clearing SS_NOFDREF
|
---|
466 | */
|
---|
467 | soisfconnecting(so);
|
---|
468 | }
|
---|
469 |
|
---|
470 | return(ret);
|
---|
471 | }
|
---|
472 |
|
---|
473 | /*
|
---|
474 | * Accept the socket and connect to the local-host
|
---|
475 | *
|
---|
476 | * We have a problem. The correct thing to do would be
|
---|
477 | * to first connect to the local-host, and only if the
|
---|
478 | * connection is accepted, then do an accept() here.
|
---|
479 | * But, a) we need to know who's trying to connect
|
---|
480 | * to the socket to be able to SYN the local-host, and
|
---|
481 | * b) we are already connected to the foreign host by
|
---|
482 | * the time it gets to accept(), so... We simply accept
|
---|
483 | * here and SYN the local-host.
|
---|
484 | */
|
---|
485 | void
|
---|
486 | tcp_connect(PNATState pData, struct socket *inso)
|
---|
487 | {
|
---|
488 | struct socket *so;
|
---|
489 | struct sockaddr_in addr;
|
---|
490 | socklen_t addrlen = sizeof(struct sockaddr_in);
|
---|
491 | struct tcpcb *tp;
|
---|
492 | int s, opt;
|
---|
493 | int status;
|
---|
494 | socklen_t optlen;
|
---|
495 | static int cVerbose = 1;
|
---|
496 |
|
---|
497 | LogFlowFunc(("ENTER: inso = %R[natsock]\n", inso));
|
---|
498 |
|
---|
499 | if ( inso->so_laddr.s_addr == INADDR_ANY /* delayed port-forwarding? */
|
---|
500 | && pData->guest_addr_guess.s_addr == INADDR_ANY)
|
---|
501 | {
|
---|
502 | LogRel2(("NAT: Port-forward: guest address unknown for %R[natsock]\n", inso));
|
---|
503 | closesocket(accept(inso->s, NULL, NULL));
|
---|
504 | if (inso->so_state & SS_FACCEPTONCE)
|
---|
505 | tcp_close(pData, sototcpcb(inso));
|
---|
506 | return;
|
---|
507 | }
|
---|
508 |
|
---|
509 | /*
|
---|
510 | * If it's an SS_ACCEPTONCE socket, no need to socreate()
|
---|
511 | * another socket, just use the accept() socket.
|
---|
512 | */
|
---|
513 | if (inso->so_state & SS_FACCEPTONCE)
|
---|
514 | {
|
---|
515 | /* FACCEPTONCE already have a tcpcb */
|
---|
516 | so = inso;
|
---|
517 | }
|
---|
518 | else
|
---|
519 | {
|
---|
520 | if ((so = socreate()) == NULL)
|
---|
521 | {
|
---|
522 | /* If it failed, get rid of the pending connection */
|
---|
523 | closesocket(accept(inso->s,(struct sockaddr *)&addr,&addrlen));
|
---|
524 | return;
|
---|
525 | }
|
---|
526 | if (tcp_attach(pData, so) < 0)
|
---|
527 | {
|
---|
528 | RTMemFree(so); /* NOT sofree */
|
---|
529 | return;
|
---|
530 | }
|
---|
531 | so->so_laddr = inso->so_laddr;
|
---|
532 | so->so_lport = inso->so_lport;
|
---|
533 | }
|
---|
534 |
|
---|
535 | if (so->so_laddr.s_addr == INADDR_ANY)
|
---|
536 | {
|
---|
537 | LogRel2(("NAT: Port-forward: using %RTnaipv4 for %R[natsock]\n",
|
---|
538 | pData->guest_addr_guess.s_addr, inso));
|
---|
539 | so->so_laddr = pData->guest_addr_guess;
|
---|
540 | }
|
---|
541 |
|
---|
542 | (void) tcp_mss(pData, sototcpcb(so), 0);
|
---|
543 |
|
---|
544 | fd_nonblock(inso->s);
|
---|
545 | if ((s = accept(inso->s,(struct sockaddr *)&addr,&addrlen)) < 0)
|
---|
546 | {
|
---|
547 | tcp_close(pData, sototcpcb(so)); /* This will sofree() as well */
|
---|
548 | return;
|
---|
549 | }
|
---|
550 | fd_nonblock(s);
|
---|
551 | opt = 1;
|
---|
552 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR,(char *)&opt, sizeof(int));
|
---|
553 | opt = 1;
|
---|
554 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE,(char *)&opt, sizeof(int));
|
---|
555 | opt = 1;
|
---|
556 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY,(char *)&opt, sizeof(int));
|
---|
557 |
|
---|
558 | optlen = sizeof(int);
|
---|
559 | status = getsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&opt, &optlen);
|
---|
560 | if (status < 0)
|
---|
561 | {
|
---|
562 | LogRel(("NAT: Error(%d) while getting RCV capacity\n", errno));
|
---|
563 | goto no_sockopt;
|
---|
564 | }
|
---|
565 | if (cVerbose > 0)
|
---|
566 | LogRel(("NAT: Old socket recv size: %dKB\n", opt / 1024));
|
---|
567 | /** @todo (r-vvl) make it configurable (via extra data) */
|
---|
568 | opt = pData->socket_rcv;
|
---|
569 | status = setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&opt, sizeof(int));
|
---|
570 | if (status < 0)
|
---|
571 | {
|
---|
572 | LogRel(("NAT: Error(%d) while setting RCV capacity to (%d)\n", errno, opt));
|
---|
573 | goto no_sockopt;
|
---|
574 | }
|
---|
575 | optlen = sizeof(int);
|
---|
576 | status = getsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&opt, &optlen);
|
---|
577 | if (status < 0)
|
---|
578 | {
|
---|
579 | LogRel(("NAT: Error(%d) while getting SND capacity\n", errno));
|
---|
580 | goto no_sockopt;
|
---|
581 | }
|
---|
582 | if (cVerbose > 0)
|
---|
583 | LogRel(("NAT: Old socket send size: %dKB\n", opt / 1024));
|
---|
584 | opt = pData->socket_rcv;
|
---|
585 | status = setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&opt, sizeof(int));
|
---|
586 | if (status < 0)
|
---|
587 | {
|
---|
588 | LogRel(("NAT: Error(%d) while setting SND capacity to (%d)\n", errno, opt));
|
---|
589 | goto no_sockopt;
|
---|
590 | }
|
---|
591 | if (cVerbose > 0)
|
---|
592 | cVerbose--;
|
---|
593 |
|
---|
594 | no_sockopt:
|
---|
595 | so->so_fport = addr.sin_port;
|
---|
596 | so->so_faddr = addr.sin_addr;
|
---|
597 | /* Translate connections from localhost to the real hostname */
|
---|
598 | if (so->so_faddr.s_addr == 0 || so->so_faddr.s_addr == loopback_addr.s_addr)
|
---|
599 | so->so_faddr = alias_addr;
|
---|
600 |
|
---|
601 | /* Close the accept() socket, set right state */
|
---|
602 | if (inso->so_state & SS_FACCEPTONCE)
|
---|
603 | {
|
---|
604 | closesocket(so->s); /* If we only accept once, close the accept() socket */
|
---|
605 | so->so_state = SS_NOFDREF; /* Don't select it yet, even though we have an FD */
|
---|
606 | /* if it's not FACCEPTONCE, it's already NOFDREF */
|
---|
607 | }
|
---|
608 | so->s = s;
|
---|
609 |
|
---|
610 | tp = sototcpcb(so);
|
---|
611 |
|
---|
612 | tcp_template(tp);
|
---|
613 |
|
---|
614 | /* Compute window scaling to request. */
|
---|
615 | /* while (tp->request_r_scale < TCP_MAX_WINSHIFT
|
---|
616 | * && (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
|
---|
617 | * tp->request_r_scale++;
|
---|
618 | */
|
---|
619 |
|
---|
620 | /* soisconnecting(so); */ /* NOFDREF used instead */
|
---|
621 | tcpstat.tcps_connattempt++;
|
---|
622 |
|
---|
623 | TCP_STATE_SWITCH_TO(tp, TCPS_SYN_SENT);
|
---|
624 | tp->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT;
|
---|
625 | tp->iss = tcp_iss;
|
---|
626 | tcp_iss += TCP_ISSINCR/2;
|
---|
627 | tcp_sendseqinit(tp);
|
---|
628 | tcp_output(pData, tp);
|
---|
629 | }
|
---|
630 |
|
---|
631 | /*
|
---|
632 | * Attach a TCPCB to a socket.
|
---|
633 | */
|
---|
634 | int
|
---|
635 | tcp_attach(PNATState pData, struct socket *so)
|
---|
636 | {
|
---|
637 | /* We're attaching already attached socket??? */
|
---|
638 | Assert(so->so_type == 0);
|
---|
639 | if ((so->so_tcpcb = tcp_newtcpcb(pData, so)) == NULL)
|
---|
640 | return -1;
|
---|
641 |
|
---|
642 | SOCKET_LOCK_CREATE(so);
|
---|
643 | QSOCKET_LOCK(tcb);
|
---|
644 | insque(pData, so, &tcb);
|
---|
645 | NSOCK_INC();
|
---|
646 | QSOCKET_UNLOCK(tcb);
|
---|
647 | return 0;
|
---|
648 | }
|
---|