1 | /* |
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2 | * dhcpcd - DHCP client daemon |
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3 | * Copyright (c) 2006-2013 Roy Marples <roy@marples.name> |
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4 | * All rights reserved |
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5 | |
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6 | * Redistribution and use in source and binary forms, with or without |
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7 | * modification, are permitted provided that the following conditions |
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8 | * are met: |
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9 | * 1. Redistributions of source code must retain the above copyright |
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10 | * notice, this list of conditions and the following disclaimer. |
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11 | * 2. Redistributions in binary form must reproduce the above copyright |
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12 | * notice, this list of conditions and the following disclaimer in the |
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13 | * documentation and/or other materials provided with the distribution. |
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14 | * |
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15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
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16 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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17 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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18 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
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19 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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20 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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21 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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22 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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23 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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24 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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25 | * SUCH DAMAGE. |
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26 | */ |
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27 | |
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28 | #include <sys/param.h> |
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29 | #include <sys/types.h> |
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30 | #include <sys/ioctl.h> |
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31 | #include <sys/socket.h> |
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32 | |
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33 | #include <net/if.h> |
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34 | #include <net/if_arp.h> |
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35 | #include <netinet/in.h> |
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36 | #ifdef __FreeBSD__ /* Needed so that including netinet6/in6_var.h works */ |
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37 | # include <net/if_var.h> |
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38 | #endif |
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39 | #ifdef AF_LINK |
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40 | # include <net/if_dl.h> |
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41 | # include <net/if_types.h> |
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42 | # include <netinet/in_var.h> |
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43 | #endif |
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44 | #ifdef AF_PACKET |
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45 | # include <netpacket/packet.h> |
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46 | #endif |
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47 | #ifdef SIOCGIFMEDIA |
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48 | # include <net/if_media.h> |
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49 | #endif |
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50 | |
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51 | #include <net/route.h> |
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52 | #ifdef __linux__ |
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53 | # include <asm/types.h> /* for systems with broken headers */ |
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54 | # include <linux/rtnetlink.h> |
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55 | #endif |
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56 | |
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57 | #include <ctype.h> |
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58 | #include <errno.h> |
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59 | #include <ifaddrs.h> |
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60 | #include <fnmatch.h> |
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61 | #include <stddef.h> |
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62 | #include <stdio.h> |
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63 | #include <stdlib.h> |
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64 | #include <string.h> |
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65 | #include <syslog.h> |
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66 | #include <unistd.h> |
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67 | |
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68 | #include "config.h" |
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69 | #include "common.h" |
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70 | #include "dev.h" |
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71 | #include "dhcp.h" |
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72 | #include "dhcp6.h" |
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73 | #include "if-options.h" |
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74 | #include "ipv4.h" |
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75 | #include "ipv6nd.h" |
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76 | #include "net.h" |
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77 | |
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78 | int socket_afnet = -1; |
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79 | |
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80 | static char hwaddr_buffer[(HWADDR_LEN * 3) + 1 + 1024]; |
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81 | |
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82 | char * |
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83 | hwaddr_ntoa(const unsigned char *hwaddr, size_t hwlen) |
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84 | { |
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85 | char *p = hwaddr_buffer; |
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86 | size_t i; |
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87 | |
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88 | for (i = 0; i < hwlen; i++) { |
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89 | if (i > 0) |
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90 | *p ++= ':'; |
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91 | p += snprintf(p, 3, "%.2x", hwaddr[i]); |
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92 | } |
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93 | |
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94 | *p ++= '\0'; |
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95 | |
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96 | return hwaddr_buffer; |
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97 | } |
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98 | |
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99 | size_t |
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100 | hwaddr_aton(unsigned char *buffer, const char *addr) |
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101 | { |
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102 | char c[3]; |
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103 | const char *p = addr; |
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104 | unsigned char *bp = buffer; |
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105 | size_t len = 0; |
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106 | |
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107 | c[2] = '\0'; |
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108 | while (*p) { |
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109 | c[0] = *p++; |
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110 | c[1] = *p++; |
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111 | /* Ensure that digits are hex */ |
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112 | if (isxdigit((unsigned char)c[0]) == 0 || |
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113 | isxdigit((unsigned char)c[1]) == 0) |
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114 | { |
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115 | errno = EINVAL; |
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116 | return 0; |
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117 | } |
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118 | /* We should have at least two entries 00:01 */ |
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119 | if (len == 0 && *p == '\0') { |
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120 | errno = EINVAL; |
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121 | return 0; |
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122 | } |
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123 | /* Ensure that next data is EOL or a seperator with data */ |
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124 | if (!(*p == '\0' || (*p == ':' && *(p + 1) != '\0'))) { |
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125 | errno = EINVAL; |
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126 | return 0; |
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127 | } |
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128 | if (*p) |
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129 | p++; |
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130 | if (bp) |
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131 | *bp++ = (unsigned char)strtol(c, NULL, 16); |
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132 | len++; |
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133 | } |
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134 | return len; |
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135 | } |
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136 | |
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137 | void |
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138 | free_interface(struct interface *ifp) |
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139 | { |
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140 | |
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141 | if (ifp == NULL) |
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142 | return; |
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143 | ipv4_free(ifp); |
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144 | dhcp_free(ifp); |
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145 | ipv6_free(ifp); |
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146 | dhcp6_free(ifp); |
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147 | ipv6nd_free(ifp); |
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148 | free_options(ifp->options); |
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149 | free(ifp); |
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150 | } |
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151 | |
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152 | int |
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153 | carrier_status(struct interface *iface) |
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154 | { |
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155 | int ret; |
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156 | struct ifreq ifr; |
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157 | #ifdef SIOCGIFMEDIA |
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158 | struct ifmediareq ifmr; |
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159 | #endif |
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160 | #ifdef __linux__ |
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161 | char *p; |
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162 | #endif |
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163 | |
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164 | memset(&ifr, 0, sizeof(ifr)); |
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165 | strlcpy(ifr.ifr_name, iface->name, sizeof(ifr.ifr_name)); |
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166 | #ifdef __linux__ |
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167 | /* We can only test the real interface up */ |
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168 | if ((p = strchr(ifr.ifr_name, ':'))) |
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169 | *p = '\0'; |
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170 | #endif |
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171 | |
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172 | if (ioctl(socket_afnet, SIOCGIFFLAGS, &ifr) == -1) |
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173 | return LINK_UNKNOWN; |
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174 | iface->flags = ifr.ifr_flags; |
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175 | |
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176 | ret = LINK_UNKNOWN; |
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177 | #ifdef SIOCGIFMEDIA |
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178 | memset(&ifmr, 0, sizeof(ifmr)); |
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179 | strlcpy(ifmr.ifm_name, iface->name, sizeof(ifmr.ifm_name)); |
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180 | if (ioctl(socket_afnet, SIOCGIFMEDIA, &ifmr) != -1 && |
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181 | ifmr.ifm_status & IFM_AVALID) |
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182 | ret = (ifmr.ifm_status & IFM_ACTIVE) ? LINK_UP : LINK_DOWN; |
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183 | #endif |
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184 | if (ret == LINK_UNKNOWN) |
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185 | ret = (ifr.ifr_flags & IFF_RUNNING) ? LINK_UP : LINK_DOWN; |
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186 | return ret; |
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187 | } |
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188 | |
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189 | int |
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190 | up_interface(struct interface *iface) |
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191 | { |
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192 | struct ifreq ifr; |
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193 | int retval = -1; |
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194 | #ifdef __linux__ |
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195 | char *p; |
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196 | #endif |
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197 | |
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198 | memset(&ifr, 0, sizeof(ifr)); |
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199 | strlcpy(ifr.ifr_name, iface->name, sizeof(ifr.ifr_name)); |
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200 | #ifdef __linux__ |
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201 | /* We can only bring the real interface up */ |
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202 | if ((p = strchr(ifr.ifr_name, ':'))) |
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203 | *p = '\0'; |
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204 | #endif |
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205 | if (ioctl(socket_afnet, SIOCGIFFLAGS, &ifr) == 0) { |
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206 | if ((ifr.ifr_flags & IFF_UP)) |
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207 | retval = 0; |
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208 | else { |
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209 | ifr.ifr_flags |= IFF_UP; |
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210 | if (ioctl(socket_afnet, SIOCSIFFLAGS, &ifr) == 0) |
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211 | retval = 0; |
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212 | } |
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213 | iface->flags = ifr.ifr_flags; |
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214 | } |
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215 | return retval; |
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216 | } |
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217 | |
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218 | struct if_head * |
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219 | discover_interfaces(int argc, char * const *argv) |
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220 | { |
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221 | struct ifaddrs *ifaddrs, *ifa; |
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222 | char *p; |
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223 | int i, sdl_type; |
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224 | struct if_head *ifs; |
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225 | struct interface *ifp; |
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226 | #ifdef __linux__ |
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227 | char ifn[IF_NAMESIZE]; |
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228 | #endif |
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229 | #ifdef INET |
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230 | const struct sockaddr_in *addr; |
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231 | const struct sockaddr_in *net; |
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232 | const struct sockaddr_in *dst; |
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233 | #endif |
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234 | #ifdef INET6 |
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235 | const struct sockaddr_in6 *sin6; |
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236 | int ifa_flags; |
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237 | #endif |
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238 | #ifdef AF_LINK |
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239 | const struct sockaddr_dl *sdl; |
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240 | #ifdef IFLR_ACTIVE |
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241 | struct if_laddrreq iflr; |
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242 | int socket_aflink; |
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243 | |
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244 | socket_aflink = socket(AF_LINK, SOCK_DGRAM, 0); |
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245 | if (socket_aflink == -1) |
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246 | return NULL; |
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247 | memset(&iflr, 0, sizeof(iflr)); |
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248 | #endif |
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249 | #elif AF_PACKET |
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250 | const struct sockaddr_ll *sll; |
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251 | #endif |
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252 | |
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253 | if (getifaddrs(&ifaddrs) == -1) |
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254 | return NULL; |
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255 | |
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256 | ifs = malloc(sizeof(*ifs)); |
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257 | if (ifs == NULL) |
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258 | return NULL; |
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259 | TAILQ_INIT(ifs); |
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260 | |
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261 | for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) { |
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262 | if (ifa->ifa_addr != NULL) { |
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263 | #ifdef AF_LINK |
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264 | if (ifa->ifa_addr->sa_family != AF_LINK) |
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265 | continue; |
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266 | #elif AF_PACKET |
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267 | if (ifa->ifa_addr->sa_family != AF_PACKET) |
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268 | continue; |
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269 | #endif |
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270 | } |
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271 | |
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272 | /* Ensure that the interface name has settled */ |
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273 | if (!dev_initialized(ifa->ifa_name)) |
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274 | continue; |
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275 | |
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276 | /* It's possible for an interface to have >1 AF_LINK. |
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277 | * For our purposes, we use the first one. */ |
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278 | TAILQ_FOREACH(ifp, ifs, next) { |
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279 | if (strcmp(ifp->name, ifa->ifa_name) == 0) |
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280 | break; |
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281 | } |
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282 | if (ifp) |
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283 | continue; |
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284 | if (argc > 0) { |
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285 | for (i = 0; i < argc; i++) { |
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286 | #ifdef __linux__ |
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287 | /* Check the real interface name */ |
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288 | strlcpy(ifn, argv[i], sizeof(ifn)); |
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289 | p = strchr(ifn, ':'); |
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290 | if (p) |
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291 | *p = '\0'; |
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292 | if (strcmp(ifn, ifa->ifa_name) == 0) |
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293 | break; |
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294 | #else |
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295 | if (strcmp(argv[i], ifa->ifa_name) == 0) |
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296 | break; |
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297 | #endif |
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298 | } |
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299 | if (i == argc) |
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300 | continue; |
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301 | p = argv[i]; |
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302 | } else { |
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303 | p = ifa->ifa_name; |
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304 | /* -1 means we're discovering against a specific |
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305 | * interface, but we still need the below rules |
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306 | * to apply. */ |
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307 | if (argc == -1 && strcmp(argv[0], ifa->ifa_name) != 0) |
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308 | continue; |
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309 | } |
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310 | for (i = 0; i < ifdc; i++) |
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311 | if (!fnmatch(ifdv[i], p, 0)) |
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312 | break; |
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313 | if (i < ifdc) |
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314 | continue; |
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315 | for (i = 0; i < ifac; i++) |
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316 | if (!fnmatch(ifav[i], p, 0)) |
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317 | break; |
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318 | if (ifac && i == ifac) |
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319 | continue; |
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320 | |
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321 | if (if_vimaster(ifa->ifa_name) == 1) { |
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322 | syslog(argc ? LOG_ERR : LOG_DEBUG, |
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323 | "%s: is a Virtual Interface Master, skipping", |
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324 | ifa->ifa_name); |
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325 | continue; |
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326 | } |
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327 | |
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328 | ifp = calloc(1, sizeof(*ifp)); |
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329 | if (ifp == NULL) |
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330 | return NULL; |
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331 | strlcpy(ifp->name, p, sizeof(ifp->name)); |
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332 | ifp->flags = ifa->ifa_flags; |
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333 | |
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334 | /* Bring the interface up if not already */ |
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335 | if (!(ifp->flags & IFF_UP) |
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336 | #ifdef SIOCGIFMEDIA |
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337 | && carrier_status(ifp) != LINK_UNKNOWN |
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338 | #endif |
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339 | ) |
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340 | { |
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341 | if (up_interface(ifp) == 0) |
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342 | options |= DHCPCD_WAITUP; |
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343 | else |
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344 | syslog(LOG_ERR, "%s: up_interface: %m", |
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345 | ifp->name); |
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346 | } |
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347 | |
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348 | sdl_type = 0; |
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349 | /* Don't allow loopback unless explicit */ |
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350 | if (ifp->flags & IFF_LOOPBACK) { |
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351 | if (argc == 0 && ifac == 0) { |
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352 | free_interface(ifp); |
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353 | continue; |
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354 | } |
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355 | } else if (ifa->ifa_addr != NULL) { |
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356 | #ifdef AF_LINK |
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357 | sdl = (const struct sockaddr_dl *)(void *)ifa->ifa_addr; |
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358 | |
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359 | #ifdef IFLR_ACTIVE |
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360 | /* We need to check for active address */ |
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361 | strlcpy(iflr.iflr_name, ifp->name, |
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362 | sizeof(iflr.iflr_name)); |
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363 | memcpy(&iflr.addr, ifa->ifa_addr, |
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364 | MIN(ifa->ifa_addr->sa_len, sizeof(iflr.addr))); |
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365 | iflr.flags = IFLR_PREFIX; |
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366 | iflr.prefixlen = sdl->sdl_alen * NBBY; |
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367 | if (ioctl(socket_aflink, SIOCGLIFADDR, &iflr) == -1 || |
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368 | !(iflr.flags & IFLR_ACTIVE)) |
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369 | { |
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370 | free_interface(ifp); |
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371 | continue; |
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372 | } |
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373 | #endif |
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374 | |
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375 | ifp->index = sdl->sdl_index; |
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376 | sdl_type = sdl->sdl_type; |
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377 | switch(sdl->sdl_type) { |
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378 | case IFT_BRIDGE: /* FALLTHROUGH */ |
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379 | case IFT_L2VLAN: /* FALLTHOUGH */ |
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380 | case IFT_L3IPVLAN: /* FALLTHROUGH */ |
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381 | case IFT_ETHER: |
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382 | ifp->family = ARPHRD_ETHER; |
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383 | break; |
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384 | case IFT_IEEE1394: |
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385 | ifp->family = ARPHRD_IEEE1394; |
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386 | break; |
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387 | #ifdef IFT_INFINIBAND |
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388 | case IFT_INFINIBAND: |
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389 | ifp->family = ARPHRD_INFINIBAND; |
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390 | break; |
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391 | #endif |
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392 | } |
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393 | ifp->hwlen = sdl->sdl_alen; |
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394 | #ifndef CLLADDR |
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395 | # define CLLADDR(s) ((const char *)((s)->sdl_data + (s)->sdl_nlen)) |
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396 | #endif |
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397 | memcpy(ifp->hwaddr, CLLADDR(sdl), ifp->hwlen); |
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398 | #elif AF_PACKET |
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399 | sll = (const struct sockaddr_ll *)(void *)ifa->ifa_addr; |
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400 | ifp->index = sll->sll_ifindex; |
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401 | ifp->family = sdl_type = sll->sll_hatype; |
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402 | ifp->hwlen = sll->sll_halen; |
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403 | if (ifp->hwlen != 0) |
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404 | memcpy(ifp->hwaddr, sll->sll_addr, ifp->hwlen); |
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405 | #endif |
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406 | } |
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407 | #ifdef __linux__ |
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408 | /* PPP addresses on Linux don't have hardware addresses */ |
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409 | else |
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410 | ifp->index = if_nametoindex(ifp->name); |
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411 | #endif |
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412 | |
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413 | /* We only work on ethernet by default */ |
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414 | if (!(ifp->flags & IFF_POINTOPOINT) && |
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415 | ifp->family != ARPHRD_ETHER) |
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416 | { |
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417 | if (argc == 0 && ifac == 0) { |
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418 | free_interface(ifp); |
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419 | continue; |
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420 | } |
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421 | switch (ifp->family) { |
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422 | case ARPHRD_IEEE1394: /* FALLTHROUGH */ |
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423 | case ARPHRD_INFINIBAND: |
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424 | /* We don't warn for supported families */ |
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425 | break; |
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426 | default: |
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427 | syslog(LOG_WARNING, |
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428 | "%s: unsupported interface type %.2x" |
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429 | ", falling back to ethernet", |
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430 | ifp->name, sdl_type); |
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431 | ifp->family = ARPHRD_ETHER; |
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432 | break; |
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433 | } |
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434 | } |
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435 | |
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436 | /* Handle any platform init for the interface */ |
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437 | if (if_init(ifp) == -1) { |
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438 | syslog(LOG_ERR, "%s: if_init: %m", p); |
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439 | free_interface(ifp); |
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440 | continue; |
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441 | } |
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442 | |
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443 | /* Ensure that the MTU is big enough for DHCP */ |
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444 | if (get_mtu(ifp->name) < MTU_MIN && |
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445 | set_mtu(ifp->name, MTU_MIN) == -1) |
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446 | { |
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447 | syslog(LOG_ERR, "%s: set_mtu: %m", p); |
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448 | free_interface(ifp); |
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449 | continue; |
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450 | } |
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451 | |
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452 | /* We reserve the 100 range for virtual interfaces, if and when |
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453 | * we can work them out. */ |
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454 | ifp->metric = 200 + ifp->index; |
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455 | if (getifssid(ifp->name, ifp->ssid) != -1) { |
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456 | ifp->wireless = 1; |
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457 | ifp->metric += 100; |
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458 | } |
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459 | |
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460 | TAILQ_INSERT_TAIL(ifs, ifp, next); |
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461 | } |
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462 | |
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463 | for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) { |
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464 | if (ifa->ifa_addr == NULL) |
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465 | continue; |
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466 | switch(ifa->ifa_addr->sa_family) { |
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467 | #ifdef INET |
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468 | case AF_INET: |
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469 | addr = (const struct sockaddr_in *) |
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470 | (void *)ifa->ifa_addr; |
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471 | net = (const struct sockaddr_in *) |
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472 | (void *)ifa->ifa_netmask; |
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473 | if (ifa->ifa_flags & IFF_POINTOPOINT) |
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474 | dst = (const struct sockaddr_in *) |
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475 | (void *)ifa->ifa_dstaddr; |
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476 | else |
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477 | dst = NULL; |
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478 | ipv4_handleifa(RTM_NEWADDR, ifs, ifa->ifa_name, |
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479 | &addr->sin_addr, |
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480 | &net->sin_addr, |
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481 | dst ? &dst->sin_addr : NULL); |
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482 | break; |
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483 | #endif |
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484 | #ifdef INET6 |
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485 | case AF_INET6: |
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486 | sin6 = (const struct sockaddr_in6 *) |
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487 | (void *)ifa->ifa_addr; |
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488 | ifa_flags = in6_addr_flags(ifa->ifa_name, |
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489 | &sin6->sin6_addr); |
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490 | if (ifa_flags != -1) |
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491 | ipv6_handleifa(RTM_NEWADDR, ifs, |
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492 | ifa->ifa_name, |
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493 | &sin6->sin6_addr, ifa_flags); |
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494 | break; |
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495 | #endif |
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496 | } |
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497 | } |
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498 | |
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499 | freeifaddrs(ifaddrs); |
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500 | |
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501 | #ifdef IFLR_ACTIVE |
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502 | close(socket_aflink); |
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503 | #endif |
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504 | |
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505 | return ifs; |
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506 | } |
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507 | |
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508 | int |
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509 | do_mtu(const char *ifname, short int mtu) |
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510 | { |
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511 | struct ifreq ifr; |
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512 | int r; |
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513 | |
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514 | memset(&ifr, 0, sizeof(ifr)); |
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515 | strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)); |
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516 | ifr.ifr_mtu = mtu; |
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517 | r = ioctl(socket_afnet, mtu ? SIOCSIFMTU : SIOCGIFMTU, &ifr); |
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518 | if (r == -1) |
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519 | return -1; |
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520 | return ifr.ifr_mtu; |
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521 | } |
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