1 | #include "port_before.h" |
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2 | |
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3 | /* |
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4 | * Copyright (c) 1985, 1989, 1993 |
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5 | * The Regents of the University of California. All rights reserved. |
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6 | * |
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7 | * Redistribution and use in source and binary forms, with or without |
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8 | * modification, are permitted provided that the following conditions |
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9 | * are met: |
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10 | * 1. Redistributions of source code must retain the above copyright |
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11 | * notice, this list of conditions and the following disclaimer. |
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12 | * 2. Redistributions in binary form must reproduce the above copyright |
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13 | * notice, this list of conditions and the following disclaimer in the |
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14 | * documentation and/or other materials provided with the distribution. |
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15 | * 4. Neither the name of the University nor the names of its contributors |
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16 | * may be used to endorse or promote products derived from this software |
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17 | * without specific prior written permission. |
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18 | * |
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19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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29 | * SUCH DAMAGE. |
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30 | */ |
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31 | |
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32 | /* |
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33 | * Portions Copyright (c) 1993 by Digital Equipment Corporation. |
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34 | * |
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35 | * Permission to use, copy, modify, and distribute this software for any |
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36 | * purpose with or without fee is hereby granted, provided that the above |
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37 | * copyright notice and this permission notice appear in all copies, and that |
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38 | * the name of Digital Equipment Corporation not be used in advertising or |
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39 | * publicity pertaining to distribution of the document or software without |
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40 | * specific, written prior permission. |
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41 | * |
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42 | * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL |
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43 | * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES |
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44 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT |
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45 | * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL |
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46 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
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47 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS |
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48 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS |
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49 | * SOFTWARE. |
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50 | */ |
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51 | |
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52 | /* |
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53 | * Copyright (c) 2005 by Internet Systems Consortium, Inc. ("ISC") |
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54 | * Portions Copyright (c) 1996-1999 by Internet Software Consortium. |
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55 | * |
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56 | * Permission to use, copy, modify, and distribute this software for any |
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57 | * purpose with or without fee is hereby granted, provided that the above |
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58 | * copyright notice and this permission notice appear in all copies. |
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59 | * |
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60 | * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES |
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61 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
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62 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR |
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63 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
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64 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
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65 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
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66 | * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
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67 | */ |
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68 | |
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69 | #if defined(LIBC_SCCS) && !defined(lint) |
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70 | static const char sccsid[] = "@(#)res_send.c 8.1 (Berkeley) 6/4/93"; |
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71 | static const char rcsid[] = "$Id: res_send.c,v 1.9.18.10 2008/01/27 02:06:26 marka Exp $"; |
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72 | #endif /* LIBC_SCCS and not lint */ |
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73 | #include <sys/cdefs.h> |
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74 | __FBSDID("$FreeBSD$"); |
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75 | |
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76 | /*! \file |
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77 | * \brief |
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78 | * Send query to name server and wait for reply. |
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79 | */ |
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80 | |
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81 | #include "port_before.h" |
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82 | #ifndef USE_KQUEUE |
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83 | #include "fd_setsize.h" |
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84 | #endif |
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85 | |
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86 | #include "namespace.h" |
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87 | #include <sys/types.h> |
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88 | #include <sys/param.h> |
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89 | #include <sys/time.h> |
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90 | #include <sys/socket.h> |
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91 | #include <sys/uio.h> |
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92 | |
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93 | #include <netinet/in.h> |
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94 | #include <arpa/nameser.h> |
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95 | #include <arpa/inet.h> |
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96 | |
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97 | #include <errno.h> |
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98 | #include <netdb.h> |
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99 | #include <resolv.h> |
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100 | #include <signal.h> |
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101 | #include <stdio.h> |
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102 | #include <stdlib.h> |
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103 | #include <string.h> |
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104 | #include <unistd.h> |
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105 | |
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106 | #include <isc/eventlib.h> |
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107 | |
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108 | #include "port_after.h" |
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109 | |
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110 | #ifdef USE_KQUEUE |
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111 | #ifdef __rtems__ |
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112 | #include <freebsd/sys/event.h> |
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113 | #else |
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114 | #include <sys/event.h> |
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115 | #endif /* __rtems__ */ |
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116 | #else |
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117 | #ifdef USE_POLL |
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118 | #ifdef HAVE_STROPTS_H |
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119 | #include <stropts.h> |
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120 | #endif |
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121 | #include <poll.h> |
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122 | #endif /* USE_POLL */ |
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123 | #endif |
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124 | |
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125 | #include "un-namespace.h" |
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126 | |
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127 | /* Options. Leave them on. */ |
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128 | #define DEBUG |
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129 | #include "res_debug.h" |
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130 | #include "res_private.h" |
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131 | |
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132 | #define EXT(res) ((res)->_u._ext) |
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133 | |
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134 | #if !defined(USE_POLL) && !defined(USE_KQUEUE) |
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135 | static const int highestFD = FD_SETSIZE - 1; |
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136 | #endif |
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137 | |
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138 | /* Forward. */ |
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139 | |
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140 | static int get_salen(const struct sockaddr *); |
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141 | static struct sockaddr * get_nsaddr(res_state, size_t); |
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142 | static int send_vc(res_state, const u_char *, int, |
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143 | u_char *, int, int *, int); |
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144 | static int send_dg(res_state, |
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145 | #ifdef USE_KQUEUE |
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146 | int kq, |
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147 | #endif |
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148 | const u_char *, int, |
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149 | u_char *, int, int *, int, int, |
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150 | int *, int *); |
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151 | static void Aerror(const res_state, FILE *, const char *, int, |
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152 | const struct sockaddr *, int); |
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153 | static void Perror(const res_state, FILE *, const char *, int); |
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154 | static int sock_eq(struct sockaddr *, struct sockaddr *); |
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155 | #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE) |
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156 | static int pselect(int, void *, void *, void *, |
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157 | struct timespec *, |
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158 | const sigset_t *); |
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159 | #endif |
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160 | void res_pquery(const res_state, const u_char *, int, FILE *); |
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161 | |
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162 | static const int niflags = NI_NUMERICHOST | NI_NUMERICSERV; |
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163 | |
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164 | /* Public. */ |
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165 | |
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166 | /*% |
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167 | * looks up "ina" in _res.ns_addr_list[] |
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168 | * |
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169 | * returns: |
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170 | *\li 0 : not found |
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171 | *\li >0 : found |
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172 | * |
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173 | * author: |
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174 | *\li paul vixie, 29may94 |
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175 | */ |
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176 | int |
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177 | res_ourserver_p(const res_state statp, const struct sockaddr *sa) { |
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178 | const struct sockaddr_in *inp, *srv; |
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179 | const struct sockaddr_in6 *in6p, *srv6; |
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180 | int ns; |
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181 | |
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182 | switch (sa->sa_family) { |
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183 | case AF_INET: |
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184 | inp = (const struct sockaddr_in *)sa; |
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185 | for (ns = 0; ns < statp->nscount; ns++) { |
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186 | srv = (struct sockaddr_in *)get_nsaddr(statp, ns); |
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187 | if (srv->sin_family == inp->sin_family && |
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188 | srv->sin_port == inp->sin_port && |
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189 | (srv->sin_addr.s_addr == INADDR_ANY || |
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190 | srv->sin_addr.s_addr == inp->sin_addr.s_addr)) |
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191 | return (1); |
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192 | } |
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193 | break; |
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194 | case AF_INET6: |
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195 | if (EXT(statp).ext == NULL) |
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196 | break; |
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197 | in6p = (const struct sockaddr_in6 *)sa; |
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198 | for (ns = 0; ns < statp->nscount; ns++) { |
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199 | srv6 = (struct sockaddr_in6 *)get_nsaddr(statp, ns); |
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200 | if (srv6->sin6_family == in6p->sin6_family && |
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201 | srv6->sin6_port == in6p->sin6_port && |
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202 | #ifdef HAVE_SIN6_SCOPE_ID |
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203 | (srv6->sin6_scope_id == 0 || |
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204 | srv6->sin6_scope_id == in6p->sin6_scope_id) && |
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205 | #endif |
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206 | (IN6_IS_ADDR_UNSPECIFIED(&srv6->sin6_addr) || |
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207 | IN6_ARE_ADDR_EQUAL(&srv6->sin6_addr, &in6p->sin6_addr))) |
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208 | return (1); |
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209 | } |
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210 | break; |
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211 | default: |
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212 | break; |
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213 | } |
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214 | return (0); |
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215 | } |
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216 | |
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217 | /*% |
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218 | * look for (name,type,class) in the query section of packet (buf,eom) |
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219 | * |
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220 | * requires: |
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221 | *\li buf + HFIXEDSZ <= eom |
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222 | * |
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223 | * returns: |
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224 | *\li -1 : format error |
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225 | *\li 0 : not found |
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226 | *\li >0 : found |
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227 | * |
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228 | * author: |
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229 | *\li paul vixie, 29may94 |
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230 | */ |
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231 | int |
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232 | res_nameinquery(const char *name, int type, int class, |
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233 | const u_char *buf, const u_char *eom) |
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234 | { |
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235 | const u_char *cp = buf + HFIXEDSZ; |
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236 | int qdcount = ntohs(((const HEADER*)buf)->qdcount); |
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237 | |
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238 | while (qdcount-- > 0) { |
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239 | char tname[MAXDNAME+1]; |
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240 | int n, ttype, tclass; |
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241 | |
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242 | n = dn_expand(buf, eom, cp, tname, sizeof tname); |
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243 | if (n < 0) |
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244 | return (-1); |
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245 | cp += n; |
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246 | if (cp + 2 * INT16SZ > eom) |
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247 | return (-1); |
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248 | ttype = ns_get16(cp); cp += INT16SZ; |
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249 | tclass = ns_get16(cp); cp += INT16SZ; |
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250 | if (ttype == type && tclass == class && |
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251 | ns_samename(tname, name) == 1) |
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252 | return (1); |
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253 | } |
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254 | return (0); |
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255 | } |
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256 | |
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257 | /*% |
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258 | * is there a 1:1 mapping of (name,type,class) |
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259 | * in (buf1,eom1) and (buf2,eom2)? |
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260 | * |
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261 | * returns: |
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262 | *\li -1 : format error |
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263 | *\li 0 : not a 1:1 mapping |
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264 | *\li >0 : is a 1:1 mapping |
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265 | * |
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266 | * author: |
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267 | *\li paul vixie, 29may94 |
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268 | */ |
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269 | int |
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270 | res_queriesmatch(const u_char *buf1, const u_char *eom1, |
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271 | const u_char *buf2, const u_char *eom2) |
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272 | { |
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273 | const u_char *cp = buf1 + HFIXEDSZ; |
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274 | int qdcount = ntohs(((const HEADER*)buf1)->qdcount); |
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275 | |
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276 | if (buf1 + HFIXEDSZ > eom1 || buf2 + HFIXEDSZ > eom2) |
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277 | return (-1); |
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278 | |
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279 | /* |
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280 | * Only header section present in replies to |
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281 | * dynamic update packets. |
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282 | */ |
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283 | if ((((const HEADER *)buf1)->opcode == ns_o_update) && |
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284 | (((const HEADER *)buf2)->opcode == ns_o_update)) |
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285 | return (1); |
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286 | |
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287 | if (qdcount != ntohs(((const HEADER*)buf2)->qdcount)) |
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288 | return (0); |
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289 | while (qdcount-- > 0) { |
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290 | char tname[MAXDNAME+1]; |
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291 | int n, ttype, tclass; |
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292 | |
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293 | n = dn_expand(buf1, eom1, cp, tname, sizeof tname); |
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294 | if (n < 0) |
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295 | return (-1); |
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296 | cp += n; |
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297 | if (cp + 2 * INT16SZ > eom1) |
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298 | return (-1); |
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299 | ttype = ns_get16(cp); cp += INT16SZ; |
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300 | tclass = ns_get16(cp); cp += INT16SZ; |
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301 | if (!res_nameinquery(tname, ttype, tclass, buf2, eom2)) |
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302 | return (0); |
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303 | } |
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304 | return (1); |
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305 | } |
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306 | |
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307 | int |
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308 | res_nsend(res_state statp, |
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309 | const u_char *buf, int buflen, u_char *ans, int anssiz) |
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310 | { |
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311 | int gotsomewhere, terrno, tries, v_circuit, resplen, ns, n; |
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312 | #ifdef USE_KQUEUE |
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313 | int kq; |
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314 | #endif |
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315 | char abuf[NI_MAXHOST]; |
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316 | |
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317 | /* No name servers or res_init() failure */ |
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318 | if (statp->nscount == 0 || EXT(statp).ext == NULL) { |
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319 | errno = ESRCH; |
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320 | return (-1); |
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321 | } |
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322 | if (anssiz < HFIXEDSZ) { |
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323 | errno = EINVAL; |
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324 | return (-1); |
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325 | } |
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326 | DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY), |
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327 | (stdout, ";; res_send()\n"), buf, buflen); |
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328 | v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ; |
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329 | gotsomewhere = 0; |
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330 | terrno = ETIMEDOUT; |
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331 | |
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332 | #ifdef USE_KQUEUE |
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333 | if ((kq = kqueue()) < 0) { |
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334 | Perror(statp, stderr, "kqueue", errno); |
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335 | return (-1); |
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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 | * If the ns_addr_list in the resolver context has changed, then |
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341 | * invalidate our cached copy and the associated timing data. |
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342 | */ |
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343 | if (EXT(statp).nscount != 0) { |
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344 | int needclose = 0; |
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345 | struct sockaddr_storage peer; |
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346 | ISC_SOCKLEN_T peerlen; |
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347 | |
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348 | if (EXT(statp).nscount != statp->nscount) |
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349 | needclose++; |
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350 | else |
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351 | for (ns = 0; ns < statp->nscount; ns++) { |
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352 | if (statp->nsaddr_list[ns].sin_family && |
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353 | !sock_eq((struct sockaddr *)&statp->nsaddr_list[ns], |
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354 | (struct sockaddr *)&EXT(statp).ext->nsaddrs[ns])) { |
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355 | needclose++; |
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356 | break; |
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357 | } |
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358 | |
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359 | if (EXT(statp).nssocks[ns] == -1) |
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360 | continue; |
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361 | peerlen = sizeof(peer); |
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362 | if (_getsockname(EXT(statp).nssocks[ns], |
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363 | (struct sockaddr *)&peer, &peerlen) < 0) { |
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364 | needclose++; |
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365 | break; |
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366 | } |
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367 | if (!sock_eq((struct sockaddr *)&peer, |
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368 | get_nsaddr(statp, ns))) { |
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369 | needclose++; |
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370 | break; |
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371 | } |
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372 | } |
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373 | if (needclose) { |
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374 | res_nclose(statp); |
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375 | EXT(statp).nscount = 0; |
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376 | } |
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377 | } |
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378 | |
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379 | /* |
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380 | * Maybe initialize our private copy of the ns_addr_list. |
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381 | */ |
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382 | if (EXT(statp).nscount == 0) { |
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383 | for (ns = 0; ns < statp->nscount; ns++) { |
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384 | EXT(statp).nstimes[ns] = RES_MAXTIME; |
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385 | EXT(statp).nssocks[ns] = -1; |
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386 | if (!statp->nsaddr_list[ns].sin_family) |
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387 | continue; |
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388 | EXT(statp).ext->nsaddrs[ns].sin = |
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389 | statp->nsaddr_list[ns]; |
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390 | } |
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391 | EXT(statp).nscount = statp->nscount; |
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392 | } |
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393 | |
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394 | /* |
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395 | * Some resolvers want to even out the load on their nameservers. |
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396 | * Note that RES_BLAST overrides RES_ROTATE. |
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397 | */ |
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398 | if ((statp->options & RES_ROTATE) != 0U && |
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399 | (statp->options & RES_BLAST) == 0U) { |
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400 | union res_sockaddr_union inu; |
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401 | struct sockaddr_in ina; |
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402 | int lastns = statp->nscount - 1; |
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403 | int fd; |
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404 | u_int16_t nstime; |
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405 | |
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406 | if (EXT(statp).ext != NULL) |
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407 | inu = EXT(statp).ext->nsaddrs[0]; |
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408 | ina = statp->nsaddr_list[0]; |
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409 | fd = EXT(statp).nssocks[0]; |
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410 | nstime = EXT(statp).nstimes[0]; |
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411 | for (ns = 0; ns < lastns; ns++) { |
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412 | if (EXT(statp).ext != NULL) |
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413 | EXT(statp).ext->nsaddrs[ns] = |
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414 | EXT(statp).ext->nsaddrs[ns + 1]; |
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415 | statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1]; |
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416 | EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1]; |
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417 | EXT(statp).nstimes[ns] = EXT(statp).nstimes[ns + 1]; |
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418 | } |
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419 | if (EXT(statp).ext != NULL) |
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420 | EXT(statp).ext->nsaddrs[lastns] = inu; |
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421 | statp->nsaddr_list[lastns] = ina; |
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422 | EXT(statp).nssocks[lastns] = fd; |
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423 | EXT(statp).nstimes[lastns] = nstime; |
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424 | } |
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425 | |
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426 | /* |
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427 | * Send request, RETRY times, or until successful. |
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428 | */ |
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429 | for (tries = 0; tries < statp->retry; tries++) { |
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430 | for (ns = 0; ns < statp->nscount; ns++) { |
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431 | struct sockaddr *nsap; |
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432 | int nsaplen; |
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433 | nsap = get_nsaddr(statp, ns); |
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434 | nsaplen = get_salen(nsap); |
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435 | statp->_flags &= ~RES_F_LASTMASK; |
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436 | statp->_flags |= (ns << RES_F_LASTSHIFT); |
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437 | same_ns: |
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438 | if (statp->qhook) { |
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439 | int done = 0, loops = 0; |
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440 | |
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441 | do { |
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442 | res_sendhookact act; |
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443 | |
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444 | act = (*statp->qhook)(&nsap, &buf, &buflen, |
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445 | ans, anssiz, &resplen); |
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446 | switch (act) { |
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447 | case res_goahead: |
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448 | done = 1; |
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449 | break; |
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450 | case res_nextns: |
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451 | res_nclose(statp); |
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452 | goto next_ns; |
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453 | case res_done: |
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454 | #ifdef USE_KQUEUE |
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455 | _close(kq); |
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456 | #endif |
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457 | return (resplen); |
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458 | case res_modified: |
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459 | /* give the hook another try */ |
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460 | if (++loops < 42) /*doug adams*/ |
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461 | break; |
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462 | /*FALLTHROUGH*/ |
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463 | case res_error: |
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464 | /*FALLTHROUGH*/ |
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465 | default: |
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466 | goto fail; |
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467 | } |
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468 | } while (!done); |
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469 | } |
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470 | |
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471 | Dprint(((statp->options & RES_DEBUG) && |
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472 | getnameinfo(nsap, nsaplen, abuf, sizeof(abuf), |
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473 | NULL, 0, niflags) == 0), |
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474 | (stdout, ";; Querying server (# %d) address = %s\n", |
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475 | ns + 1, abuf)); |
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476 | |
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477 | |
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478 | if (v_circuit) { |
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479 | /* Use VC; at most one attempt per server. */ |
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480 | tries = statp->retry; |
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481 | n = send_vc(statp, buf, buflen, ans, anssiz, &terrno, |
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482 | ns); |
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483 | if (n < 0) |
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484 | goto fail; |
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485 | if (n == 0) |
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486 | goto next_ns; |
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487 | resplen = n; |
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488 | } else { |
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489 | /* Use datagrams. */ |
---|
490 | n = send_dg(statp, |
---|
491 | #ifdef USE_KQUEUE |
---|
492 | kq, |
---|
493 | #endif |
---|
494 | buf, buflen, ans, anssiz, &terrno, |
---|
495 | ns, tries, &v_circuit, &gotsomewhere); |
---|
496 | if (n < 0) |
---|
497 | goto fail; |
---|
498 | if (n == 0) |
---|
499 | goto next_ns; |
---|
500 | if (v_circuit) |
---|
501 | goto same_ns; |
---|
502 | resplen = n; |
---|
503 | } |
---|
504 | |
---|
505 | Dprint((statp->options & RES_DEBUG) || |
---|
506 | ((statp->pfcode & RES_PRF_REPLY) && |
---|
507 | (statp->pfcode & RES_PRF_HEAD1)), |
---|
508 | (stdout, ";; got answer:\n")); |
---|
509 | |
---|
510 | DprintQ((statp->options & RES_DEBUG) || |
---|
511 | (statp->pfcode & RES_PRF_REPLY), |
---|
512 | (stdout, "%s", ""), |
---|
513 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
514 | |
---|
515 | /* |
---|
516 | * If we have temporarily opened a virtual circuit, |
---|
517 | * or if we haven't been asked to keep a socket open, |
---|
518 | * close the socket. |
---|
519 | */ |
---|
520 | if ((v_circuit && (statp->options & RES_USEVC) == 0U) || |
---|
521 | (statp->options & RES_STAYOPEN) == 0U) { |
---|
522 | res_nclose(statp); |
---|
523 | } |
---|
524 | if (statp->rhook) { |
---|
525 | int done = 0, loops = 0; |
---|
526 | |
---|
527 | do { |
---|
528 | res_sendhookact act; |
---|
529 | |
---|
530 | act = (*statp->rhook)(nsap, buf, buflen, |
---|
531 | ans, anssiz, &resplen); |
---|
532 | switch (act) { |
---|
533 | case res_goahead: |
---|
534 | case res_done: |
---|
535 | done = 1; |
---|
536 | break; |
---|
537 | case res_nextns: |
---|
538 | res_nclose(statp); |
---|
539 | goto next_ns; |
---|
540 | case res_modified: |
---|
541 | /* give the hook another try */ |
---|
542 | if (++loops < 42) /*doug adams*/ |
---|
543 | break; |
---|
544 | /*FALLTHROUGH*/ |
---|
545 | case res_error: |
---|
546 | /*FALLTHROUGH*/ |
---|
547 | default: |
---|
548 | goto fail; |
---|
549 | } |
---|
550 | } while (!done); |
---|
551 | |
---|
552 | } |
---|
553 | #ifdef USE_KQUEUE |
---|
554 | _close(kq); |
---|
555 | #endif |
---|
556 | return (resplen); |
---|
557 | next_ns: ; |
---|
558 | } /*foreach ns*/ |
---|
559 | } /*foreach retry*/ |
---|
560 | res_nclose(statp); |
---|
561 | #ifdef USE_KQUEUE |
---|
562 | _close(kq); |
---|
563 | #endif |
---|
564 | if (!v_circuit) { |
---|
565 | if (!gotsomewhere) |
---|
566 | errno = ECONNREFUSED; /*%< no nameservers found */ |
---|
567 | else |
---|
568 | errno = ETIMEDOUT; /*%< no answer obtained */ |
---|
569 | } else |
---|
570 | errno = terrno; |
---|
571 | return (-1); |
---|
572 | fail: |
---|
573 | res_nclose(statp); |
---|
574 | #ifdef USE_KQUEUE |
---|
575 | _close(kq); |
---|
576 | #endif |
---|
577 | return (-1); |
---|
578 | } |
---|
579 | |
---|
580 | /* Private */ |
---|
581 | |
---|
582 | static int |
---|
583 | get_salen(sa) |
---|
584 | const struct sockaddr *sa; |
---|
585 | { |
---|
586 | |
---|
587 | #ifdef HAVE_SA_LEN |
---|
588 | /* There are people do not set sa_len. Be forgiving to them. */ |
---|
589 | if (sa->sa_len) |
---|
590 | return (sa->sa_len); |
---|
591 | #endif |
---|
592 | |
---|
593 | if (sa->sa_family == AF_INET) |
---|
594 | return (sizeof(struct sockaddr_in)); |
---|
595 | else if (sa->sa_family == AF_INET6) |
---|
596 | return (sizeof(struct sockaddr_in6)); |
---|
597 | else |
---|
598 | return (0); /*%< unknown, die on connect */ |
---|
599 | } |
---|
600 | |
---|
601 | /*% |
---|
602 | * pick appropriate nsaddr_list for use. see res_init() for initialization. |
---|
603 | */ |
---|
604 | static struct sockaddr * |
---|
605 | get_nsaddr(statp, n) |
---|
606 | res_state statp; |
---|
607 | size_t n; |
---|
608 | { |
---|
609 | |
---|
610 | if (!statp->nsaddr_list[n].sin_family && EXT(statp).ext) { |
---|
611 | /* |
---|
612 | * - EXT(statp).ext->nsaddrs[n] holds an address that is larger |
---|
613 | * than struct sockaddr, and |
---|
614 | * - user code did not update statp->nsaddr_list[n]. |
---|
615 | */ |
---|
616 | return (struct sockaddr *)(void *)&EXT(statp).ext->nsaddrs[n]; |
---|
617 | } else { |
---|
618 | /* |
---|
619 | * - user code updated statp->nsaddr_list[n], or |
---|
620 | * - statp->nsaddr_list[n] has the same content as |
---|
621 | * EXT(statp).ext->nsaddrs[n]. |
---|
622 | */ |
---|
623 | return (struct sockaddr *)(void *)&statp->nsaddr_list[n]; |
---|
624 | } |
---|
625 | } |
---|
626 | |
---|
627 | static int |
---|
628 | send_vc(res_state statp, |
---|
629 | const u_char *buf, int buflen, u_char *ans, int anssiz, |
---|
630 | int *terrno, int ns) |
---|
631 | { |
---|
632 | const HEADER *hp = (const HEADER *) buf; |
---|
633 | HEADER *anhp = (HEADER *) ans; |
---|
634 | struct sockaddr *nsap; |
---|
635 | int nsaplen; |
---|
636 | int truncating, connreset, resplen, n; |
---|
637 | struct iovec iov[2]; |
---|
638 | u_short len; |
---|
639 | u_char *cp; |
---|
640 | void *tmp; |
---|
641 | #ifdef SO_NOSIGPIPE |
---|
642 | int on = 1; |
---|
643 | #endif |
---|
644 | |
---|
645 | nsap = get_nsaddr(statp, ns); |
---|
646 | nsaplen = get_salen(nsap); |
---|
647 | |
---|
648 | connreset = 0; |
---|
649 | same_ns: |
---|
650 | truncating = 0; |
---|
651 | |
---|
652 | /* Are we still talking to whom we want to talk to? */ |
---|
653 | if (statp->_vcsock >= 0 && (statp->_flags & RES_F_VC) != 0) { |
---|
654 | struct sockaddr_storage peer; |
---|
655 | ISC_SOCKLEN_T size = sizeof peer; |
---|
656 | |
---|
657 | if (_getpeername(statp->_vcsock, |
---|
658 | (struct sockaddr *)&peer, &size) < 0 || |
---|
659 | !sock_eq((struct sockaddr *)&peer, nsap)) { |
---|
660 | res_nclose(statp); |
---|
661 | statp->_flags &= ~RES_F_VC; |
---|
662 | } |
---|
663 | } |
---|
664 | |
---|
665 | if (statp->_vcsock < 0 || (statp->_flags & RES_F_VC) == 0) { |
---|
666 | if (statp->_vcsock >= 0) |
---|
667 | res_nclose(statp); |
---|
668 | |
---|
669 | statp->_vcsock = _socket(nsap->sa_family, SOCK_STREAM, 0); |
---|
670 | #if !defined(USE_POLL) && !defined(USE_KQUEUE) |
---|
671 | if (statp->_vcsock > highestFD) { |
---|
672 | res_nclose(statp); |
---|
673 | errno = ENOTSOCK; |
---|
674 | } |
---|
675 | #endif |
---|
676 | if (statp->_vcsock < 0) { |
---|
677 | switch (errno) { |
---|
678 | case EPROTONOSUPPORT: |
---|
679 | #ifdef EPFNOSUPPORT |
---|
680 | case EPFNOSUPPORT: |
---|
681 | #endif |
---|
682 | case EAFNOSUPPORT: |
---|
683 | Perror(statp, stderr, "socket(vc)", errno); |
---|
684 | return (0); |
---|
685 | default: |
---|
686 | *terrno = errno; |
---|
687 | Perror(statp, stderr, "socket(vc)", errno); |
---|
688 | return (-1); |
---|
689 | } |
---|
690 | } |
---|
691 | #ifdef SO_NOSIGPIPE |
---|
692 | /* |
---|
693 | * Disable generation of SIGPIPE when writing to a closed |
---|
694 | * socket. Write should return -1 and set errno to EPIPE |
---|
695 | * instead. |
---|
696 | * |
---|
697 | * Push on even if setsockopt(SO_NOSIGPIPE) fails. |
---|
698 | */ |
---|
699 | (void)_setsockopt(statp->_vcsock, SOL_SOCKET, SO_NOSIGPIPE, &on, |
---|
700 | sizeof(on)); |
---|
701 | #endif |
---|
702 | errno = 0; |
---|
703 | if (_connect(statp->_vcsock, nsap, nsaplen) < 0) { |
---|
704 | *terrno = errno; |
---|
705 | Aerror(statp, stderr, "connect/vc", errno, nsap, |
---|
706 | nsaplen); |
---|
707 | res_nclose(statp); |
---|
708 | return (0); |
---|
709 | } |
---|
710 | statp->_flags |= RES_F_VC; |
---|
711 | } |
---|
712 | |
---|
713 | /* |
---|
714 | * Send length & message |
---|
715 | */ |
---|
716 | ns_put16((u_short)buflen, (u_char*)&len); |
---|
717 | iov[0] = evConsIovec(&len, INT16SZ); |
---|
718 | DE_CONST(buf, tmp); |
---|
719 | iov[1] = evConsIovec(tmp, buflen); |
---|
720 | if (_writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) { |
---|
721 | *terrno = errno; |
---|
722 | Perror(statp, stderr, "write failed", errno); |
---|
723 | res_nclose(statp); |
---|
724 | return (0); |
---|
725 | } |
---|
726 | /* |
---|
727 | * Receive length & response |
---|
728 | */ |
---|
729 | read_len: |
---|
730 | cp = ans; |
---|
731 | len = INT16SZ; |
---|
732 | while ((n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) { |
---|
733 | cp += n; |
---|
734 | if ((len -= n) == 0) |
---|
735 | break; |
---|
736 | } |
---|
737 | if (n <= 0) { |
---|
738 | *terrno = errno; |
---|
739 | Perror(statp, stderr, "read failed", errno); |
---|
740 | res_nclose(statp); |
---|
741 | /* |
---|
742 | * A long running process might get its TCP |
---|
743 | * connection reset if the remote server was |
---|
744 | * restarted. Requery the server instead of |
---|
745 | * trying a new one. When there is only one |
---|
746 | * server, this means that a query might work |
---|
747 | * instead of failing. We only allow one reset |
---|
748 | * per query to prevent looping. |
---|
749 | */ |
---|
750 | if (*terrno == ECONNRESET && !connreset) { |
---|
751 | connreset = 1; |
---|
752 | res_nclose(statp); |
---|
753 | goto same_ns; |
---|
754 | } |
---|
755 | res_nclose(statp); |
---|
756 | return (0); |
---|
757 | } |
---|
758 | resplen = ns_get16(ans); |
---|
759 | if (resplen > anssiz) { |
---|
760 | Dprint(statp->options & RES_DEBUG, |
---|
761 | (stdout, ";; response truncated\n") |
---|
762 | ); |
---|
763 | truncating = 1; |
---|
764 | len = anssiz; |
---|
765 | } else |
---|
766 | len = resplen; |
---|
767 | if (len < HFIXEDSZ) { |
---|
768 | /* |
---|
769 | * Undersized message. |
---|
770 | */ |
---|
771 | Dprint(statp->options & RES_DEBUG, |
---|
772 | (stdout, ";; undersized: %d\n", len)); |
---|
773 | *terrno = EMSGSIZE; |
---|
774 | res_nclose(statp); |
---|
775 | return (0); |
---|
776 | } |
---|
777 | cp = ans; |
---|
778 | while (len != 0 && |
---|
779 | (n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) { |
---|
780 | cp += n; |
---|
781 | len -= n; |
---|
782 | } |
---|
783 | if (n <= 0) { |
---|
784 | *terrno = errno; |
---|
785 | Perror(statp, stderr, "read(vc)", errno); |
---|
786 | res_nclose(statp); |
---|
787 | return (0); |
---|
788 | } |
---|
789 | if (truncating) { |
---|
790 | /* |
---|
791 | * Flush rest of answer so connection stays in synch. |
---|
792 | */ |
---|
793 | anhp->tc = 1; |
---|
794 | len = resplen - anssiz; |
---|
795 | while (len != 0) { |
---|
796 | char junk[PACKETSZ]; |
---|
797 | |
---|
798 | n = _read(statp->_vcsock, junk, |
---|
799 | (len > sizeof junk) ? sizeof junk : len); |
---|
800 | if (n > 0) |
---|
801 | len -= n; |
---|
802 | else |
---|
803 | break; |
---|
804 | } |
---|
805 | } |
---|
806 | /* |
---|
807 | * If the calling applicating has bailed out of |
---|
808 | * a previous call and failed to arrange to have |
---|
809 | * the circuit closed or the server has got |
---|
810 | * itself confused, then drop the packet and |
---|
811 | * wait for the correct one. |
---|
812 | */ |
---|
813 | if (hp->id != anhp->id) { |
---|
814 | DprintQ((statp->options & RES_DEBUG) || |
---|
815 | (statp->pfcode & RES_PRF_REPLY), |
---|
816 | (stdout, ";; old answer (unexpected):\n"), |
---|
817 | ans, (resplen > anssiz) ? anssiz: resplen); |
---|
818 | goto read_len; |
---|
819 | } |
---|
820 | |
---|
821 | /* |
---|
822 | * All is well, or the error is fatal. Signal that the |
---|
823 | * next nameserver ought not be tried. |
---|
824 | */ |
---|
825 | return (resplen); |
---|
826 | } |
---|
827 | |
---|
828 | static int |
---|
829 | send_dg(res_state statp, |
---|
830 | #ifdef USE_KQUEUE |
---|
831 | int kq, |
---|
832 | #endif |
---|
833 | const u_char *buf, int buflen, u_char *ans, |
---|
834 | int anssiz, int *terrno, int ns, int tries, int *v_circuit, |
---|
835 | int *gotsomewhere) |
---|
836 | { |
---|
837 | const HEADER *hp = (const HEADER *) buf; |
---|
838 | HEADER *anhp = (HEADER *) ans; |
---|
839 | const struct sockaddr *nsap; |
---|
840 | int nsaplen; |
---|
841 | struct timespec now, timeout, finish; |
---|
842 | struct sockaddr_storage from; |
---|
843 | ISC_SOCKLEN_T fromlen; |
---|
844 | int resplen, seconds, n, s; |
---|
845 | #ifdef USE_KQUEUE |
---|
846 | struct kevent kv; |
---|
847 | #else |
---|
848 | #ifdef USE_POLL |
---|
849 | int polltimeout; |
---|
850 | struct pollfd pollfd; |
---|
851 | #else |
---|
852 | fd_set dsmask; |
---|
853 | #endif |
---|
854 | #endif |
---|
855 | |
---|
856 | nsap = get_nsaddr(statp, ns); |
---|
857 | nsaplen = get_salen(nsap); |
---|
858 | if (EXT(statp).nssocks[ns] == -1) { |
---|
859 | EXT(statp).nssocks[ns] = _socket(nsap->sa_family, |
---|
860 | SOCK_DGRAM, 0); |
---|
861 | #if !defined(USE_POLL) && !defined(USE_KQUEUE) |
---|
862 | if (EXT(statp).nssocks[ns] > highestFD) { |
---|
863 | res_nclose(statp); |
---|
864 | errno = ENOTSOCK; |
---|
865 | } |
---|
866 | #endif |
---|
867 | if (EXT(statp).nssocks[ns] < 0) { |
---|
868 | switch (errno) { |
---|
869 | case EPROTONOSUPPORT: |
---|
870 | #ifdef EPFNOSUPPORT |
---|
871 | case EPFNOSUPPORT: |
---|
872 | #endif |
---|
873 | case EAFNOSUPPORT: |
---|
874 | Perror(statp, stderr, "socket(dg)", errno); |
---|
875 | return (0); |
---|
876 | default: |
---|
877 | *terrno = errno; |
---|
878 | Perror(statp, stderr, "socket(dg)", errno); |
---|
879 | return (-1); |
---|
880 | } |
---|
881 | } |
---|
882 | #ifndef CANNOT_CONNECT_DGRAM |
---|
883 | /* |
---|
884 | * On a 4.3BSD+ machine (client and server, |
---|
885 | * actually), sending to a nameserver datagram |
---|
886 | * port with no nameserver will cause an |
---|
887 | * ICMP port unreachable message to be returned. |
---|
888 | * If our datagram socket is "connected" to the |
---|
889 | * server, we get an ECONNREFUSED error on the next |
---|
890 | * socket operation, and select returns if the |
---|
891 | * error message is received. We can thus detect |
---|
892 | * the absence of a nameserver without timing out. |
---|
893 | * |
---|
894 | * When the option "insecure1" is specified, we'd |
---|
895 | * rather expect to see responses from an "unknown" |
---|
896 | * address. In order to let the kernel accept such |
---|
897 | * responses, do not connect the socket here. |
---|
898 | * XXX: or do we need an explicit option to disable |
---|
899 | * connecting? |
---|
900 | */ |
---|
901 | if (!(statp->options & RES_INSECURE1) && |
---|
902 | _connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) { |
---|
903 | Aerror(statp, stderr, "connect(dg)", errno, nsap, |
---|
904 | nsaplen); |
---|
905 | res_nclose(statp); |
---|
906 | return (0); |
---|
907 | } |
---|
908 | #endif /* !CANNOT_CONNECT_DGRAM */ |
---|
909 | Dprint(statp->options & RES_DEBUG, |
---|
910 | (stdout, ";; new DG socket\n")) |
---|
911 | } |
---|
912 | s = EXT(statp).nssocks[ns]; |
---|
913 | #ifndef CANNOT_CONNECT_DGRAM |
---|
914 | if (statp->options & RES_INSECURE1) { |
---|
915 | if (_sendto(s, |
---|
916 | (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) { |
---|
917 | Aerror(statp, stderr, "sendto", errno, nsap, nsaplen); |
---|
918 | res_nclose(statp); |
---|
919 | return (0); |
---|
920 | } |
---|
921 | } else if (send(s, (const char*)buf, buflen, 0) != buflen) { |
---|
922 | Perror(statp, stderr, "send", errno); |
---|
923 | res_nclose(statp); |
---|
924 | return (0); |
---|
925 | } |
---|
926 | #else /* !CANNOT_CONNECT_DGRAM */ |
---|
927 | if (_sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) |
---|
928 | { |
---|
929 | Aerror(statp, stderr, "sendto", errno, nsap, nsaplen); |
---|
930 | res_nclose(statp); |
---|
931 | return (0); |
---|
932 | } |
---|
933 | #endif /* !CANNOT_CONNECT_DGRAM */ |
---|
934 | |
---|
935 | /* |
---|
936 | * Wait for reply. |
---|
937 | */ |
---|
938 | seconds = (statp->retrans << tries); |
---|
939 | if (ns > 0) |
---|
940 | seconds /= statp->nscount; |
---|
941 | if (seconds <= 0) |
---|
942 | seconds = 1; |
---|
943 | now = evNowTime(); |
---|
944 | timeout = evConsTime(seconds, 0); |
---|
945 | finish = evAddTime(now, timeout); |
---|
946 | goto nonow; |
---|
947 | wait: |
---|
948 | now = evNowTime(); |
---|
949 | nonow: |
---|
950 | #ifndef USE_POLL |
---|
951 | if (evCmpTime(finish, now) > 0) |
---|
952 | timeout = evSubTime(finish, now); |
---|
953 | else |
---|
954 | timeout = evConsTime(0, 0); |
---|
955 | #ifdef USE_KQUEUE |
---|
956 | EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, 0); |
---|
957 | n = _kevent(kq, &kv, 1, &kv, 1, &timeout); |
---|
958 | #else |
---|
959 | FD_ZERO(&dsmask); |
---|
960 | FD_SET(s, &dsmask); |
---|
961 | n = pselect(s + 1, &dsmask, NULL, NULL, &timeout, NULL); |
---|
962 | #endif |
---|
963 | #else |
---|
964 | timeout = evSubTime(finish, now); |
---|
965 | if (timeout.tv_sec < 0) |
---|
966 | timeout = evConsTime(0, 0); |
---|
967 | polltimeout = 1000*timeout.tv_sec + |
---|
968 | timeout.tv_nsec/1000000; |
---|
969 | pollfd.fd = s; |
---|
970 | pollfd.events = POLLRDNORM; |
---|
971 | n = poll(&pollfd, 1, polltimeout); |
---|
972 | #endif /* USE_POLL */ |
---|
973 | |
---|
974 | if (n == 0) { |
---|
975 | Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n")); |
---|
976 | *gotsomewhere = 1; |
---|
977 | return (0); |
---|
978 | } |
---|
979 | if (n < 0) { |
---|
980 | if (errno == EINTR) |
---|
981 | goto wait; |
---|
982 | #ifdef USE_KQUEUE |
---|
983 | Perror(statp, stderr, "kevent", errno); |
---|
984 | #else |
---|
985 | #ifndef USE_POLL |
---|
986 | Perror(statp, stderr, "select", errno); |
---|
987 | #else |
---|
988 | Perror(statp, stderr, "poll", errno); |
---|
989 | #endif /* USE_POLL */ |
---|
990 | #endif |
---|
991 | res_nclose(statp); |
---|
992 | return (0); |
---|
993 | } |
---|
994 | #ifdef USE_KQUEUE |
---|
995 | if (kv.ident != s) |
---|
996 | goto wait; |
---|
997 | #endif |
---|
998 | errno = 0; |
---|
999 | fromlen = sizeof(from); |
---|
1000 | resplen = _recvfrom(s, (char*)ans, anssiz,0, |
---|
1001 | (struct sockaddr *)&from, &fromlen); |
---|
1002 | if (resplen <= 0) { |
---|
1003 | Perror(statp, stderr, "recvfrom", errno); |
---|
1004 | res_nclose(statp); |
---|
1005 | return (0); |
---|
1006 | } |
---|
1007 | *gotsomewhere = 1; |
---|
1008 | if (resplen < HFIXEDSZ) { |
---|
1009 | /* |
---|
1010 | * Undersized message. |
---|
1011 | */ |
---|
1012 | Dprint(statp->options & RES_DEBUG, |
---|
1013 | (stdout, ";; undersized: %d\n", |
---|
1014 | resplen)); |
---|
1015 | *terrno = EMSGSIZE; |
---|
1016 | res_nclose(statp); |
---|
1017 | return (0); |
---|
1018 | } |
---|
1019 | if (hp->id != anhp->id) { |
---|
1020 | /* |
---|
1021 | * response from old query, ignore it. |
---|
1022 | * XXX - potential security hazard could |
---|
1023 | * be detected here. |
---|
1024 | */ |
---|
1025 | DprintQ((statp->options & RES_DEBUG) || |
---|
1026 | (statp->pfcode & RES_PRF_REPLY), |
---|
1027 | (stdout, ";; old answer:\n"), |
---|
1028 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
1029 | goto wait; |
---|
1030 | } |
---|
1031 | if (!(statp->options & RES_INSECURE1) && |
---|
1032 | !res_ourserver_p(statp, (struct sockaddr *)&from)) { |
---|
1033 | /* |
---|
1034 | * response from wrong server? ignore it. |
---|
1035 | * XXX - potential security hazard could |
---|
1036 | * be detected here. |
---|
1037 | */ |
---|
1038 | DprintQ((statp->options & RES_DEBUG) || |
---|
1039 | (statp->pfcode & RES_PRF_REPLY), |
---|
1040 | (stdout, ";; not our server:\n"), |
---|
1041 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
1042 | goto wait; |
---|
1043 | } |
---|
1044 | #ifdef RES_USE_EDNS0 |
---|
1045 | if (anhp->rcode == FORMERR && (statp->options & RES_USE_EDNS0) != 0U) { |
---|
1046 | /* |
---|
1047 | * Do not retry if the server do not understand EDNS0. |
---|
1048 | * The case has to be captured here, as FORMERR packet do not |
---|
1049 | * carry query section, hence res_queriesmatch() returns 0. |
---|
1050 | */ |
---|
1051 | DprintQ(statp->options & RES_DEBUG, |
---|
1052 | (stdout, "server rejected query with EDNS0:\n"), |
---|
1053 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
1054 | /* record the error */ |
---|
1055 | statp->_flags |= RES_F_EDNS0ERR; |
---|
1056 | res_nclose(statp); |
---|
1057 | return (0); |
---|
1058 | } |
---|
1059 | #endif |
---|
1060 | if (!(statp->options & RES_INSECURE2) && |
---|
1061 | !res_queriesmatch(buf, buf + buflen, |
---|
1062 | ans, ans + anssiz)) { |
---|
1063 | /* |
---|
1064 | * response contains wrong query? ignore it. |
---|
1065 | * XXX - potential security hazard could |
---|
1066 | * be detected here. |
---|
1067 | */ |
---|
1068 | DprintQ((statp->options & RES_DEBUG) || |
---|
1069 | (statp->pfcode & RES_PRF_REPLY), |
---|
1070 | (stdout, ";; wrong query name:\n"), |
---|
1071 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
1072 | goto wait; |
---|
1073 | } |
---|
1074 | if (anhp->rcode == SERVFAIL || |
---|
1075 | anhp->rcode == NOTIMP || |
---|
1076 | anhp->rcode == REFUSED) { |
---|
1077 | DprintQ(statp->options & RES_DEBUG, |
---|
1078 | (stdout, "server rejected query:\n"), |
---|
1079 | ans, (resplen > anssiz) ? anssiz : resplen); |
---|
1080 | res_nclose(statp); |
---|
1081 | /* don't retry if called from dig */ |
---|
1082 | if (!statp->pfcode) |
---|
1083 | return (0); |
---|
1084 | } |
---|
1085 | if (!(statp->options & RES_IGNTC) && anhp->tc) { |
---|
1086 | /* |
---|
1087 | * To get the rest of answer, |
---|
1088 | * use TCP with same server. |
---|
1089 | */ |
---|
1090 | Dprint(statp->options & RES_DEBUG, |
---|
1091 | (stdout, ";; truncated answer\n")); |
---|
1092 | *v_circuit = 1; |
---|
1093 | res_nclose(statp); |
---|
1094 | return (1); |
---|
1095 | } |
---|
1096 | /* |
---|
1097 | * All is well, or the error is fatal. Signal that the |
---|
1098 | * next nameserver ought not be tried. |
---|
1099 | */ |
---|
1100 | return (resplen); |
---|
1101 | } |
---|
1102 | |
---|
1103 | static void |
---|
1104 | Aerror(const res_state statp, FILE *file, const char *string, int error, |
---|
1105 | const struct sockaddr *address, int alen) |
---|
1106 | { |
---|
1107 | int save = errno; |
---|
1108 | char hbuf[NI_MAXHOST]; |
---|
1109 | char sbuf[NI_MAXSERV]; |
---|
1110 | |
---|
1111 | alen = alen; |
---|
1112 | |
---|
1113 | if ((statp->options & RES_DEBUG) != 0U) { |
---|
1114 | if (getnameinfo(address, alen, hbuf, sizeof(hbuf), |
---|
1115 | sbuf, sizeof(sbuf), niflags)) { |
---|
1116 | strncpy(hbuf, "?", sizeof(hbuf) - 1); |
---|
1117 | hbuf[sizeof(hbuf) - 1] = '\0'; |
---|
1118 | strncpy(sbuf, "?", sizeof(sbuf) - 1); |
---|
1119 | sbuf[sizeof(sbuf) - 1] = '\0'; |
---|
1120 | } |
---|
1121 | fprintf(file, "res_send: %s ([%s].%s): %s\n", |
---|
1122 | string, hbuf, sbuf, strerror(error)); |
---|
1123 | } |
---|
1124 | errno = save; |
---|
1125 | } |
---|
1126 | |
---|
1127 | static void |
---|
1128 | Perror(const res_state statp, FILE *file, const char *string, int error) { |
---|
1129 | int save = errno; |
---|
1130 | |
---|
1131 | if ((statp->options & RES_DEBUG) != 0U) |
---|
1132 | fprintf(file, "res_send: %s: %s\n", |
---|
1133 | string, strerror(error)); |
---|
1134 | errno = save; |
---|
1135 | } |
---|
1136 | |
---|
1137 | static int |
---|
1138 | sock_eq(struct sockaddr *a, struct sockaddr *b) { |
---|
1139 | struct sockaddr_in *a4, *b4; |
---|
1140 | struct sockaddr_in6 *a6, *b6; |
---|
1141 | |
---|
1142 | if (a->sa_family != b->sa_family) |
---|
1143 | return 0; |
---|
1144 | switch (a->sa_family) { |
---|
1145 | case AF_INET: |
---|
1146 | a4 = (struct sockaddr_in *)a; |
---|
1147 | b4 = (struct sockaddr_in *)b; |
---|
1148 | return a4->sin_port == b4->sin_port && |
---|
1149 | a4->sin_addr.s_addr == b4->sin_addr.s_addr; |
---|
1150 | case AF_INET6: |
---|
1151 | a6 = (struct sockaddr_in6 *)a; |
---|
1152 | b6 = (struct sockaddr_in6 *)b; |
---|
1153 | return a6->sin6_port == b6->sin6_port && |
---|
1154 | #ifdef HAVE_SIN6_SCOPE_ID |
---|
1155 | a6->sin6_scope_id == b6->sin6_scope_id && |
---|
1156 | #endif |
---|
1157 | IN6_ARE_ADDR_EQUAL(&a6->sin6_addr, &b6->sin6_addr); |
---|
1158 | default: |
---|
1159 | return 0; |
---|
1160 | } |
---|
1161 | } |
---|
1162 | |
---|
1163 | #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE) |
---|
1164 | /* XXX needs to move to the porting library. */ |
---|
1165 | static int |
---|
1166 | pselect(int nfds, void *rfds, void *wfds, void *efds, |
---|
1167 | struct timespec *tsp, const sigset_t *sigmask) |
---|
1168 | { |
---|
1169 | struct timeval tv, *tvp; |
---|
1170 | sigset_t sigs; |
---|
1171 | int n; |
---|
1172 | |
---|
1173 | if (tsp) { |
---|
1174 | tvp = &tv; |
---|
1175 | tv = evTimeVal(*tsp); |
---|
1176 | } else |
---|
1177 | tvp = NULL; |
---|
1178 | if (sigmask) |
---|
1179 | sigprocmask(SIG_SETMASK, sigmask, &sigs); |
---|
1180 | n = select(nfds, rfds, wfds, efds, tvp); |
---|
1181 | if (sigmask) |
---|
1182 | sigprocmask(SIG_SETMASK, &sigs, NULL); |
---|
1183 | if (tsp) |
---|
1184 | *tsp = evTimeSpec(tv); |
---|
1185 | return (n); |
---|
1186 | } |
---|
1187 | #endif |
---|