| 1 | /* $Id: udp.c 98103 2023-01-17 14:15:46Z vboxsync $ */
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| 2 | /** @file
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| 3 | * NAT - UDP protocol.
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| 4 | */
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| 5 |
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| 6 | /*
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| 7 | * Copyright (C) 2006-2023 Oracle and/or its affiliates.
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| 8 | *
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| 9 | * This file is part of VirtualBox base platform packages, as
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| 10 | * available from https://www.virtualbox.org.
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| 11 | *
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| 12 | * This program is free software; you can redistribute it and/or
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| 13 | * modify it under the terms of the GNU General Public License
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| 14 | * as published by the Free Software Foundation, in version 3 of the
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| 15 | * License.
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| 16 | *
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| 17 | * This program is distributed in the hope that it will be useful, but
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| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of
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| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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| 20 | * General Public License for more details.
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| 21 | *
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| 22 | * You should have received a copy of the GNU General Public License
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| 23 | * along with this program; if not, see <https://www.gnu.org/licenses>.
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| 24 | *
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| 25 | * SPDX-License-Identifier: GPL-3.0-only
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| 26 | */
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| 27 |
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| 28 | /*
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| 29 | * This code is based on:
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| 30 | *
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| 31 | * Copyright (c) 1982, 1986, 1988, 1990, 1993
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| 32 | * The Regents of the University of California. All rights reserved.
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| 33 | *
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| 34 | * Redistribution and use in source and binary forms, with or without
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| 35 | * modification, are permitted provided that the following conditions
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| 36 | * are met:
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| 37 | * 1. Redistributions of source code must retain the above copyright
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| 38 | * notice, this list of conditions and the following disclaimer.
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| 39 | * 2. Redistributions in binary form must reproduce the above copyright
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| 40 | * notice, this list of conditions and the following disclaimer in the
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| 41 | * documentation and/or other materials provided with the distribution.
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| 42 | * 3. Neither the name of the University nor the names of its contributors
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| 43 | * may be used to endorse or promote products derived from this software
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| 44 | * without specific prior written permission.
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| 45 | *
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| 46 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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| 47 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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| 48 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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| 49 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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| 50 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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| 51 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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| 52 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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| 53 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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| 54 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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| 55 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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| 56 | * SUCH DAMAGE.
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| 57 | *
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| 58 | * @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94
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| 59 | * udp_usrreq.c,v 1.4 1994/10/02 17:48:45 phk Exp
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| 60 | */
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| 61 |
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| 62 | /*
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| 63 | * Changes and additions relating to SLiRP
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| 64 | * Copyright (c) 1995 Danny Gasparovski.
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| 65 | *
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| 66 | * Please read the file COPYRIGHT for the
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| 67 | * terms and conditions of the copyright.
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| 68 | */
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| 69 |
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| 70 | #include <slirp.h>
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| 71 | #include "ip_icmp.h"
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| 72 |
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| 73 |
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| 74 | /*
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| 75 | * UDP protocol implementation.
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| 76 | * Per RFC 768, August, 1980.
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| 77 | */
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| 78 | #define udpcksum 1
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| 79 |
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| 80 | void
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| 81 | udp_init(PNATState pData)
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| 82 | {
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| 83 | udp_last_so = &udb;
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| 84 | udb.so_next = udb.so_prev = &udb;
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| 85 | }
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| 86 |
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| 87 | /* m->m_data points at ip packet header
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| 88 | * m->m_len length ip packet
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| 89 | * ip->ip_len length data (IPDU)
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| 90 | */
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| 91 | void
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| 92 | udp_input(PNATState pData, register struct mbuf *m, int iphlen)
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| 93 | {
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| 94 | register struct ip *ip;
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| 95 | register struct udphdr *uh;
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| 96 | int len;
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| 97 | struct ip save_ip;
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| 98 | struct socket *so;
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| 99 | int ret;
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| 100 | int ttl, tos;
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| 101 |
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| 102 | LogFlowFunc(("ENTER: m = %p, iphlen = %d\n", m, iphlen));
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| 103 | ip = mtod(m, struct ip *);
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| 104 | Log2(("%RTnaipv4 iphlen = %d\n", ip->ip_dst, iphlen));
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| 105 |
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| 106 | udpstat.udps_ipackets++;
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| 107 |
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| 108 | /*
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| 109 | * Strip IP options, if any; should skip this,
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| 110 | * make available to user, and use on returned packets,
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| 111 | * but we don't yet have a way to check the checksum
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| 112 | * with options still present.
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| 113 | */
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| 114 | if (iphlen > sizeof(struct ip))
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| 115 | {
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| 116 | ip_stripoptions(m, (struct mbuf *)0);
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| 117 | iphlen = sizeof(struct ip);
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| 118 | }
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| 119 |
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| 120 | /*
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| 121 | * Get IP and UDP header together in first mbuf.
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| 122 | */
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| 123 | ip = mtod(m, struct ip *);
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| 124 | uh = (struct udphdr *)((caddr_t)ip + iphlen);
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| 125 |
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| 126 | /*
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| 127 | * Make mbuf data length reflect UDP length.
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| 128 | * If not enough data to reflect UDP length, drop.
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| 129 | */
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| 130 | len = RT_N2H_U16((u_int16_t)uh->uh_ulen);
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| 131 | Assert(ip->ip_len + iphlen == (ssize_t)m_length(m, NULL));
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| 132 |
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| 133 | if (ip->ip_len != len)
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| 134 | {
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| 135 | if (len > ip->ip_len)
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| 136 | {
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| 137 | udpstat.udps_badlen++;
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| 138 | Log3(("NAT: IP(id: %hd) has bad size\n", ip->ip_id));
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| 139 | goto bad_free_mbuf;
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| 140 | }
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| 141 | m_adj(m, len - ip->ip_len);
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| 142 | ip->ip_len = len;
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| 143 | }
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| 144 |
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| 145 | /*
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| 146 | * Save a copy of the IP header in case we want restore it
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| 147 | * for sending an ICMP error message in response.
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| 148 | */
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| 149 | save_ip = *ip;
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| 150 | save_ip.ip_len+= iphlen; /* tcp_input subtracts this */
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| 151 |
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| 152 | /*
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| 153 | * Checksum extended UDP header and data.
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| 154 | */
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| 155 | if (udpcksum && uh->uh_sum)
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| 156 | {
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| 157 | memset(((struct ipovly *)ip)->ih_x1, 0, 9);
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| 158 | ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
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| 159 | #if 0
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| 160 | /* keep uh_sum for ICMP reply */
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| 161 | uh->uh_sum = cksum(m, len + sizeof (struct ip));
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| 162 | if (uh->uh_sum)
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| 163 | {
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| 164 |
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| 165 | #endif
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| 166 | if (cksum(m, len + iphlen))
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| 167 | {
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| 168 | udpstat.udps_badsum++;
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| 169 | Log3(("NAT: IP(id: %hd) has bad (udp) cksum\n", ip->ip_id));
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| 170 | goto bad_free_mbuf;
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| 171 | }
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| 172 | }
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| 173 | #if 0
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| 174 | }
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| 175 | #endif
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| 176 |
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| 177 | /*
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| 178 | * handle DHCP/BOOTP
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| 179 | */
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| 180 | if (uh->uh_dport == RT_H2N_U16_C(BOOTP_SERVER))
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| 181 | {
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| 182 | bootp_input(pData, m);
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| 183 | goto done_free_mbuf;
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| 184 | }
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| 185 |
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| 186 | LogFunc(("uh src: %RTnaipv4:%d, dst: %RTnaipv4:%d\n",
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| 187 | ip->ip_src.s_addr, RT_N2H_U16(uh->uh_sport),
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| 188 | ip->ip_dst.s_addr, RT_N2H_U16(uh->uh_dport)));
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| 189 |
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| 190 | /*
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| 191 | * handle DNS host resolver without creating a socket
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| 192 | */
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| 193 | if ( pData->fUseHostResolver
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| 194 | && uh->uh_dport == RT_H2N_U16_C(53)
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| 195 | && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS))
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| 196 | {
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| 197 | struct sockaddr_in dst, src;
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| 198 |
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| 199 | src.sin_addr.s_addr = ip->ip_dst.s_addr;
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| 200 | src.sin_port = uh->uh_dport;
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| 201 | dst.sin_addr.s_addr = ip->ip_src.s_addr;
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| 202 | dst.sin_port = uh->uh_sport;
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| 203 |
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| 204 | m_adj(m, sizeof(struct udpiphdr));
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| 205 |
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| 206 | m = hostresolver(pData, m, ip->ip_src.s_addr, uh->uh_sport);
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| 207 | if (m == NULL)
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| 208 | goto done_free_mbuf;
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| 209 |
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| 210 | slirpMbufTagService(pData, m, CTL_DNS);
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| 211 |
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| 212 | udp_output2(pData, NULL, m, &src, &dst, IPTOS_LOWDELAY);
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| 213 | LogFlowFuncLeave();
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| 214 | return;
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| 215 | }
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| 216 |
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| 217 | /*
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| 218 | * handle TFTP
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| 219 | */
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| 220 | if ( uh->uh_dport == RT_H2N_U16_C(TFTP_SERVER)
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| 221 | && CTL_CHECK(ip->ip_dst.s_addr, CTL_TFTP))
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| 222 | {
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| 223 | if (pData->pvTftpSessions)
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| 224 | slirpTftpInput(pData, m);
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| 225 | goto done_free_mbuf;
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| 226 | }
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| 227 |
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| 228 | /*
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| 229 | * XXX: DNS proxy currently relies on the fact that each socket
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| 230 | * only serves one request.
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| 231 | */
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| 232 | if ( pData->fUseDnsProxy
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| 233 | && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS)
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| 234 | && (uh->uh_dport == RT_H2N_U16_C(53)))
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| 235 | {
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| 236 | so = NULL;
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| 237 | goto new_socket;
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| 238 | }
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| 239 |
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| 240 | /*
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| 241 | * Drop UDP packets destind for CTL_ALIAS (i.e. the hosts loopback interface)
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| 242 | * if it is disabled.
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| 243 | */
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| 244 | if ( CTL_CHECK(ip->ip_dst.s_addr, CTL_ALIAS)
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| 245 | && !pData->fLocalhostReachable)
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| 246 | goto done_free_mbuf;
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| 247 |
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| 248 | /*
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| 249 | * Locate pcb for datagram.
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| 250 | */
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| 251 | so = udp_last_so;
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| 252 | if ( so->so_lport != uh->uh_sport
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| 253 | || so->so_laddr.s_addr != ip->ip_src.s_addr)
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| 254 | {
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| 255 | struct socket *tmp;
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| 256 |
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| 257 | for (tmp = udb.so_next; tmp != &udb; tmp = tmp->so_next)
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| 258 | {
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| 259 | if ( tmp->so_lport == uh->uh_sport
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| 260 | && tmp->so_laddr.s_addr == ip->ip_src.s_addr)
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| 261 | {
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| 262 | so = tmp;
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| 263 | break;
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| 264 | }
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| 265 | }
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| 266 | if (tmp == &udb)
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| 267 | so = NULL;
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| 268 | else
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| 269 | {
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| 270 | udpstat.udpps_pcbcachemiss++;
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| 271 | udp_last_so = so;
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| 272 | }
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| 273 | }
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| 274 |
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| 275 | new_socket:
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| 276 | if (so == NULL)
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| 277 | {
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| 278 | /*
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| 279 | * If there's no socket for this packet,
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| 280 | * create one
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| 281 | */
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| 282 | if ((so = socreate()) == NULL)
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| 283 | {
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| 284 | Log2(("NAT: IP(id: %hd) failed to create socket\n", ip->ip_id));
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| 285 | goto bad_free_mbuf;
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| 286 | }
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| 287 |
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| 288 | /*
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| 289 | * Setup fields
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| 290 | */
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| 291 | so->so_laddr = ip->ip_src;
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| 292 | so->so_lport = uh->uh_sport;
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| 293 | so->so_iptos = ip->ip_tos;
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| 294 |
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| 295 | if (udp_attach(pData, so) <= 0)
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| 296 | {
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| 297 | Log2(("NAT: IP(id: %hd) udp_attach errno = %d (%s)\n",
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| 298 | ip->ip_id, errno, strerror(errno)));
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| 299 | sofree(pData, so);
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| 300 | goto bad_free_mbuf;
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| 301 | }
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| 302 |
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| 303 | /* udp_last_so = so; */
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| 304 | /*
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| 305 | * XXXXX Here, check if it's in udpexec_list,
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| 306 | * and if it is, do the fork_exec() etc.
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| 307 | */
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| 308 | }
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| 309 |
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| 310 | so->so_faddr = ip->ip_dst; /* XXX */
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| 311 | so->so_fport = uh->uh_dport; /* XXX */
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| 312 | Assert(so->so_type == IPPROTO_UDP);
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| 313 |
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| 314 | /*
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| 315 | * DNS proxy
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| 316 | */
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| 317 | if ( pData->fUseDnsProxy
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| 318 | && CTL_CHECK(ip->ip_dst.s_addr, CTL_DNS)
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| 319 | && (uh->uh_dport == RT_H2N_U16_C(53)))
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| 320 | {
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| 321 | dnsproxy_query(pData, so, m, iphlen);
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| 322 | goto done_free_mbuf;
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| 323 | }
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| 324 |
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| 325 | iphlen += sizeof(struct udphdr);
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| 326 | m->m_len -= iphlen;
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| 327 | m->m_data += iphlen;
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| 328 |
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| 329 | ttl = ip->ip_ttl = save_ip.ip_ttl;
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| 330 | if (ttl != so->so_sottl) {
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| 331 | ret = setsockopt(so->s, IPPROTO_IP, IP_TTL,
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| 332 | (char *)&ttl, sizeof(ttl));
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| 333 | if (RT_LIKELY(ret == 0))
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| 334 | so->so_sottl = ttl;
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| 335 | }
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| 336 |
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| 337 | tos = save_ip.ip_tos;
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| 338 | if (tos != so->so_sotos) {
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| 339 | ret = setsockopt(so->s, IPPROTO_IP, IP_TOS,
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| 340 | (char *)&tos, sizeof(tos));
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| 341 | if (RT_LIKELY(ret == 0))
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| 342 | so->so_sotos = tos;
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| 343 | }
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| 344 |
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| 345 | {
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| 346 | /*
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| 347 | * Different OSes have different socket options for DF. We
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| 348 | * can't use IP_HDRINCL here as it's only valid for SOCK_RAW.
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| 349 | */
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| 350 | # define USE_DF_OPTION(_Optname) \
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| 351 | const int dfopt = _Optname
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| 352 | #if defined(IP_MTU_DISCOVER)
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| 353 | USE_DF_OPTION(IP_MTU_DISCOVER);
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| 354 | #elif defined(IP_DONTFRAG) /* Solaris 11+, FreeBSD */
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| 355 | USE_DF_OPTION(IP_DONTFRAG);
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| 356 | #elif defined(IP_DONTFRAGMENT) /* Windows */
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| 357 | USE_DF_OPTION(IP_DONTFRAGMENT);
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| 358 | #else
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| 359 | USE_DF_OPTION(0);
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| 360 | #endif
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| 361 | if (dfopt) {
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| 362 | int df = (save_ip.ip_off & IP_DF) != 0;
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| 363 | #if defined(IP_MTU_DISCOVER)
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| 364 | df = df ? IP_PMTUDISC_DO : IP_PMTUDISC_DONT;
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| 365 | #endif
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| 366 | if (df != so->so_sodf) {
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| 367 | ret = setsockopt(so->s, IPPROTO_IP, dfopt,
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| 368 | (char *)&df, sizeof(df));
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| 369 | if (RT_LIKELY(ret == 0))
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| 370 | so->so_sodf = df;
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| 371 | }
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| 372 | }
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| 373 | }
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| 374 |
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| 375 | if ( sosendto(pData, so, m) == -1
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| 376 | && ( !soIgnorableErrorCode(errno)
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| 377 | && errno != ENOTCONN))
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| 378 | {
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| 379 | m->m_len += iphlen;
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| 380 | m->m_data -= iphlen;
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| 381 | *ip = save_ip;
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| 382 | Log2(("NAT: UDP tx errno = %d (%s) on sent to %RTnaipv4\n",
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| 383 | errno, strerror(errno), ip->ip_dst));
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| 384 | icmp_error(pData, m, ICMP_UNREACH, ICMP_UNREACH_NET, 0, strerror(errno));
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| 385 | so->so_m = NULL;
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| 386 | LogFlowFuncLeave();
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| 387 | return;
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| 388 | }
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| 389 |
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| 390 | if (so->so_m)
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| 391 | m_freem(pData, so->so_m); /* used for ICMP if error on sorecvfrom */
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| 392 |
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| 393 | /* restore the orig mbuf packet */
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| 394 | m->m_len += iphlen;
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| 395 | m->m_data -= iphlen;
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| 396 | *ip = save_ip;
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| 397 | so->so_m = m; /* ICMP backup */
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| 398 | LogFlowFuncLeave();
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| 399 | return;
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| 400 |
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| 401 | bad_free_mbuf:
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| 402 | Log2(("NAT: UDP(id: %hd) datagram to %RTnaipv4 with size(%d) claimed as bad\n",
|
|---|
| 403 | ip->ip_id, &ip->ip_dst, ip->ip_len));
|
|---|
| 404 |
|
|---|
| 405 | done_free_mbuf:
|
|---|
| 406 | /* some services like bootp(built-in), dns(buildt-in) and dhcp don't need sockets
|
|---|
| 407 | * and create new m'buffers to send them to guest, so we'll free their incomming
|
|---|
| 408 | * buffers here.
|
|---|
| 409 | */
|
|---|
| 410 | if (m != NULL)
|
|---|
| 411 | m_freem(pData, m);
|
|---|
| 412 | LogFlowFuncLeave();
|
|---|
| 413 | return;
|
|---|
| 414 | }
|
|---|
| 415 |
|
|---|
| 416 | /**
|
|---|
| 417 | * Output a UDP packet.
|
|---|
| 418 | *
|
|---|
| 419 | * @note This function will finally free m!
|
|---|
| 420 | */
|
|---|
| 421 | int udp_output2(PNATState pData, struct socket *so, struct mbuf *m,
|
|---|
| 422 | struct sockaddr_in *saddr, struct sockaddr_in *daddr,
|
|---|
| 423 | int iptos)
|
|---|
| 424 | {
|
|---|
| 425 | register struct udpiphdr *ui;
|
|---|
| 426 | int error;
|
|---|
| 427 | int mlen = 0;
|
|---|
| 428 |
|
|---|
| 429 | LogFlowFunc(("ENTER: so = %R[natsock], m = %p, saddr = %RTnaipv4, daddr = %RTnaipv4\n",
|
|---|
| 430 | so, m, saddr->sin_addr.s_addr, daddr->sin_addr.s_addr));
|
|---|
| 431 |
|
|---|
| 432 | /* in case of built-in service so might be NULL */
|
|---|
| 433 | if (so) Assert(so->so_type == IPPROTO_UDP);
|
|---|
| 434 |
|
|---|
| 435 | /*
|
|---|
| 436 | * Adjust for header
|
|---|
| 437 | */
|
|---|
| 438 | m->m_data -= sizeof(struct udpiphdr);
|
|---|
| 439 | m->m_len += sizeof(struct udpiphdr);
|
|---|
| 440 | mlen = m_length(m, NULL);
|
|---|
| 441 |
|
|---|
| 442 | /*
|
|---|
| 443 | * Fill in mbuf with extended UDP header
|
|---|
| 444 | * and addresses and length put into network format.
|
|---|
| 445 | */
|
|---|
| 446 | ui = mtod(m, struct udpiphdr *);
|
|---|
| 447 | memset(ui->ui_x1, 0, 9);
|
|---|
| 448 | ui->ui_pr = IPPROTO_UDP;
|
|---|
| 449 | ui->ui_len = RT_H2N_U16((uint16_t)(mlen - sizeof(struct ip)));
|
|---|
| 450 | /* XXXXX Check for from-one-location sockets, or from-any-location sockets */
|
|---|
| 451 | ui->ui_src = saddr->sin_addr;
|
|---|
| 452 | ui->ui_dst = daddr->sin_addr;
|
|---|
| 453 | ui->ui_sport = saddr->sin_port;
|
|---|
| 454 | ui->ui_dport = daddr->sin_port;
|
|---|
| 455 | ui->ui_ulen = ui->ui_len;
|
|---|
| 456 |
|
|---|
| 457 | /*
|
|---|
| 458 | * Stuff checksum and output datagram.
|
|---|
| 459 | */
|
|---|
| 460 | ui->ui_sum = 0;
|
|---|
| 461 | if (udpcksum)
|
|---|
| 462 | {
|
|---|
| 463 | if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ mlen)) == 0)
|
|---|
| 464 | ui->ui_sum = 0xffff;
|
|---|
| 465 | }
|
|---|
| 466 | ((struct ip *)ui)->ip_len = mlen;
|
|---|
| 467 | ((struct ip *)ui)->ip_ttl = ip_defttl;
|
|---|
| 468 | ((struct ip *)ui)->ip_tos = iptos;
|
|---|
| 469 |
|
|---|
| 470 | udpstat.udps_opackets++;
|
|---|
| 471 |
|
|---|
| 472 | error = ip_output(pData, so, m);
|
|---|
| 473 |
|
|---|
| 474 | return error;
|
|---|
| 475 | }
|
|---|
| 476 |
|
|---|
| 477 | /**
|
|---|
| 478 | * @note This function will free m!
|
|---|
| 479 | */
|
|---|
| 480 | int udp_output(PNATState pData, struct socket *so, struct mbuf *m,
|
|---|
| 481 | struct sockaddr_in *addr)
|
|---|
| 482 | {
|
|---|
| 483 | struct sockaddr_in saddr, daddr;
|
|---|
| 484 |
|
|---|
| 485 | Assert(so->so_type == IPPROTO_UDP);
|
|---|
| 486 | LogFlowFunc(("ENTER: so = %R[natsock], m = %p, saddr = %RTnaipv4\n", so, m, addr->sin_addr.s_addr));
|
|---|
| 487 |
|
|---|
| 488 | if (so->so_laddr.s_addr == INADDR_ANY)
|
|---|
| 489 | {
|
|---|
| 490 | if (pData->guest_addr_guess.s_addr != INADDR_ANY)
|
|---|
| 491 | {
|
|---|
| 492 | LogRel2(("NAT: port-forward: using %RTnaipv4 for %R[natsock]\n",
|
|---|
| 493 | pData->guest_addr_guess.s_addr, so));
|
|---|
| 494 | so->so_laddr = pData->guest_addr_guess;
|
|---|
| 495 | }
|
|---|
| 496 | else
|
|---|
| 497 | {
|
|---|
| 498 | LogRel2(("NAT: port-forward: guest address unknown for %R[natsock]\n", so));
|
|---|
| 499 | m_freem(pData, m);
|
|---|
| 500 | return 0;
|
|---|
| 501 | }
|
|---|
| 502 | }
|
|---|
| 503 |
|
|---|
| 504 | saddr = *addr;
|
|---|
| 505 | if ((so->so_faddr.s_addr & RT_H2N_U32(pData->netmask)) == pData->special_addr.s_addr)
|
|---|
| 506 | {
|
|---|
| 507 | saddr.sin_addr.s_addr = so->so_faddr.s_addr;
|
|---|
| 508 | if (slirpIsWideCasting(pData, so->so_faddr.s_addr))
|
|---|
| 509 | {
|
|---|
| 510 | /**
|
|---|
| 511 | * We haven't got real firewall but have got its submodule libalias.
|
|---|
| 512 | */
|
|---|
| 513 | m->m_flags |= M_SKIP_FIREWALL;
|
|---|
| 514 | /**
|
|---|
| 515 | * udp/137 port is Name Service in NetBIOS protocol. for some reasons Windows guest rejects
|
|---|
| 516 | * accept data from non-aliased server.
|
|---|
| 517 | */
|
|---|
| 518 | if ( (so->so_fport == so->so_lport)
|
|---|
| 519 | && (so->so_fport == RT_H2N_U16(137)))
|
|---|
| 520 | saddr.sin_addr.s_addr = alias_addr.s_addr;
|
|---|
| 521 | else
|
|---|
| 522 | saddr.sin_addr.s_addr = addr->sin_addr.s_addr;
|
|---|
| 523 | so->so_faddr.s_addr = addr->sin_addr.s_addr;
|
|---|
| 524 | }
|
|---|
| 525 | }
|
|---|
| 526 |
|
|---|
| 527 | /* Any UDP packet to the loopback address must be translated to be from
|
|---|
| 528 | * the forwarding address, i.e. 10.0.2.2. */
|
|---|
| 529 | if ( (saddr.sin_addr.s_addr & RT_H2N_U32_C(IN_CLASSA_NET))
|
|---|
| 530 | == RT_H2N_U32_C(INADDR_LOOPBACK & IN_CLASSA_NET))
|
|---|
| 531 | saddr.sin_addr.s_addr = alias_addr.s_addr;
|
|---|
| 532 |
|
|---|
| 533 | daddr.sin_addr = so->so_laddr;
|
|---|
| 534 | daddr.sin_port = so->so_lport;
|
|---|
| 535 |
|
|---|
| 536 | return udp_output2(pData, so, m, &saddr, &daddr, so->so_iptos);
|
|---|
| 537 | }
|
|---|
| 538 |
|
|---|
| 539 | int
|
|---|
| 540 | udp_attach(PNATState pData, struct socket *so)
|
|---|
| 541 | {
|
|---|
| 542 | struct sockaddr sa_addr;
|
|---|
| 543 | socklen_t socklen = sizeof(struct sockaddr);
|
|---|
| 544 | int status;
|
|---|
| 545 | int opt = 1;
|
|---|
| 546 |
|
|---|
| 547 | AssertReturn(so->so_type == 0, -1);
|
|---|
| 548 | so->so_type = IPPROTO_UDP;
|
|---|
| 549 |
|
|---|
| 550 | so->s = socket(AF_INET, SOCK_DGRAM, 0);
|
|---|
| 551 | if (so->s == -1)
|
|---|
| 552 | goto error;
|
|---|
| 553 | fd_nonblock(so->s);
|
|---|
| 554 |
|
|---|
| 555 | so->so_sottl = 0;
|
|---|
| 556 | so->so_sotos = 0;
|
|---|
| 557 | so->so_sodf = -1;
|
|---|
| 558 |
|
|---|
| 559 | status = sobind(pData, so);
|
|---|
| 560 | if (status != 0)
|
|---|
| 561 | return status;
|
|---|
| 562 |
|
|---|
| 563 | /* success, insert in queue */
|
|---|
| 564 | so->so_expire = curtime + SO_EXPIRE;
|
|---|
| 565 |
|
|---|
| 566 | /* enable broadcast for later use */
|
|---|
| 567 | setsockopt(so->s, SOL_SOCKET, SO_BROADCAST, (const char *)&opt, sizeof(opt));
|
|---|
| 568 |
|
|---|
| 569 | status = getsockname(so->s, &sa_addr, &socklen);
|
|---|
| 570 | if (status == 0)
|
|---|
| 571 | {
|
|---|
| 572 | Assert(sa_addr.sa_family == AF_INET);
|
|---|
| 573 | so->so_hlport = ((struct sockaddr_in *)&sa_addr)->sin_port;
|
|---|
| 574 | so->so_hladdr.s_addr = ((struct sockaddr_in *)&sa_addr)->sin_addr.s_addr;
|
|---|
| 575 | }
|
|---|
| 576 |
|
|---|
| 577 | SOCKET_LOCK_CREATE(so);
|
|---|
| 578 | QSOCKET_LOCK(udb);
|
|---|
| 579 | insque(pData, so, &udb);
|
|---|
| 580 | NSOCK_INC();
|
|---|
| 581 | QSOCKET_UNLOCK(udb);
|
|---|
| 582 | return so->s;
|
|---|
| 583 | error:
|
|---|
| 584 | Log2(("NAT: can't create datagram socket\n"));
|
|---|
| 585 | return -1;
|
|---|
| 586 | }
|
|---|
| 587 |
|
|---|
| 588 | void
|
|---|
| 589 | udp_detach(PNATState pData, struct socket *so)
|
|---|
| 590 | {
|
|---|
| 591 | if (so != &pData->icmp_socket)
|
|---|
| 592 | {
|
|---|
| 593 | Assert(so->so_type == IPPROTO_UDP);
|
|---|
| 594 | QSOCKET_LOCK(udb);
|
|---|
| 595 | SOCKET_LOCK(so);
|
|---|
| 596 | QSOCKET_UNLOCK(udb);
|
|---|
| 597 | closesocket(so->s);
|
|---|
| 598 | sofree(pData, so);
|
|---|
| 599 | SOCKET_UNLOCK(so);
|
|---|
| 600 | }
|
|---|
| 601 | }
|
|---|
| 602 |
|
|---|
| 603 | struct socket *
|
|---|
| 604 | udp_listen(PNATState pData, u_int32_t bind_addr, u_int port, u_int32_t laddr, u_int lport, int flags)
|
|---|
| 605 | {
|
|---|
| 606 | struct sockaddr_in addr;
|
|---|
| 607 | struct socket *so;
|
|---|
| 608 | socklen_t addrlen = sizeof(struct sockaddr_in);
|
|---|
| 609 | int opt = 1;
|
|---|
| 610 | LogFlowFunc(("ENTER: bind_addr:%RTnaipv4, port:%d, laddr:%RTnaipv4, lport:%d, flags:%x\n",
|
|---|
| 611 | bind_addr, RT_N2H_U16(port), laddr, RT_N2H_U16(lport), flags));
|
|---|
| 612 |
|
|---|
| 613 | if ((so = socreate()) == NULL)
|
|---|
| 614 | {
|
|---|
| 615 | LogFlowFunc(("LEAVE: NULL\n"));
|
|---|
| 616 | return NULL;
|
|---|
| 617 | }
|
|---|
| 618 |
|
|---|
| 619 | so->s = socket(AF_INET, SOCK_DGRAM, 0);
|
|---|
| 620 | if (so->s == -1)
|
|---|
| 621 | {
|
|---|
| 622 | LogRel(("NAT: can't create datagram socket\n"));
|
|---|
| 623 | RTMemFree(so);
|
|---|
| 624 | LogFlowFunc(("LEAVE: NULL\n"));
|
|---|
| 625 | return NULL;
|
|---|
| 626 | }
|
|---|
| 627 | so->so_expire = curtime + SO_EXPIRE;
|
|---|
| 628 | so->so_type = IPPROTO_UDP;
|
|---|
| 629 | fd_nonblock(so->s);
|
|---|
| 630 | so->so_sottl = 0;
|
|---|
| 631 | so->so_sotos = 0;
|
|---|
| 632 | so->so_sodf = -1;
|
|---|
| 633 | SOCKET_LOCK_CREATE(so);
|
|---|
| 634 | QSOCKET_LOCK(udb);
|
|---|
| 635 | insque(pData, so, &udb);
|
|---|
| 636 | NSOCK_INC();
|
|---|
| 637 | QSOCKET_UNLOCK(udb);
|
|---|
| 638 |
|
|---|
| 639 | memset(&addr, 0, sizeof(addr));
|
|---|
| 640 | #ifdef RT_OS_DARWIN
|
|---|
| 641 | addr.sin_len = sizeof(addr);
|
|---|
| 642 | #endif
|
|---|
| 643 | addr.sin_family = AF_INET;
|
|---|
| 644 | addr.sin_addr.s_addr = bind_addr;
|
|---|
| 645 | addr.sin_port = port;
|
|---|
| 646 |
|
|---|
| 647 | if (bind(so->s,(struct sockaddr *)&addr, addrlen) < 0)
|
|---|
| 648 | {
|
|---|
| 649 | LogRel(("NAT: udp bind to %RTnaipv4:%d failed, error %d\n",
|
|---|
| 650 | addr.sin_addr, RT_N2H_U16(port), errno));
|
|---|
| 651 | udp_detach(pData, so);
|
|---|
| 652 | LogFlowFunc(("LEAVE: NULL\n"));
|
|---|
| 653 | return NULL;
|
|---|
| 654 | }
|
|---|
| 655 | setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR,(char *)&opt, sizeof(int));
|
|---|
| 656 | /* setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE,(char *)&opt, sizeof(int)); */
|
|---|
| 657 |
|
|---|
| 658 | getsockname(so->s,(struct sockaddr *)&addr,&addrlen);
|
|---|
| 659 | so->so_hladdr = addr.sin_addr;
|
|---|
| 660 | so->so_hlport = addr.sin_port;
|
|---|
| 661 |
|
|---|
| 662 | /* XXX: wtf are we setting so_faddr/so_fport here? */
|
|---|
| 663 | so->so_fport = addr.sin_port;
|
|---|
| 664 | #if 0
|
|---|
| 665 | /* The original check was completely broken, as the commented out
|
|---|
| 666 | * if statement was always true (INADDR_ANY=0). */
|
|---|
| 667 | /** @todo vvl - alias_addr should be set (if required)
|
|---|
| 668 | * later by liabalias module.
|
|---|
| 669 | */
|
|---|
| 670 | if (addr.sin_addr.s_addr == 0 || addr.sin_addr.s_addr == loopback_addr.s_addr)
|
|---|
| 671 | so->so_faddr = alias_addr;
|
|---|
| 672 | else
|
|---|
| 673 | #endif
|
|---|
| 674 | so->so_faddr = addr.sin_addr;
|
|---|
| 675 |
|
|---|
| 676 | so->so_lport = lport;
|
|---|
| 677 | so->so_laddr.s_addr = laddr;
|
|---|
| 678 | if (flags != SS_FACCEPTONCE)
|
|---|
| 679 | so->so_expire = 0;
|
|---|
| 680 |
|
|---|
| 681 | so->so_state = SS_ISFCONNECTED;
|
|---|
| 682 |
|
|---|
| 683 | LogFlowFunc(("LEAVE: %R[natsock]\n", so));
|
|---|
| 684 | return so;
|
|---|
| 685 | }
|
|---|
