1 # Generate /etc/resolv.conf 2 # Support resolvconf(8) if available 3 # We can merge other dhcpcd resolv.conf files into one like resolvconf, 4 # but resolvconf is preferred as other applications like VPN clients 5 # can readily hook into it. 6 # Also, resolvconf can configure local nameservers such as bind 7 # or dnsmasq. This is important as the libc resolver isn't that powerful. 8 9 resolv_conf_dir="$state_dir/resolv.conf" 10 11 build_resolv_conf() 12 { 13 local cf="$state_dir/resolv.conf.$interface" 14 local interfaces= header= search= srvs= servers= x= 15 16 # Build a list of interfaces 17 interfaces=$(list_interfaces "$resolv_conf_dir") 18 19 # Build the resolv.conf 20 if [ -n "$interfaces" ]; then 21 # Build the header 22 for x in ${interfaces}; do 23 header="$header${header:+, }$x" 24 done 25 26 # Build the search list 27 domain=$(cd "$resolv_conf_dir"; \ 28 key_get_value "domain " ${interfaces}) 29 search=$(cd "$resolv_conf_dir"; \ 30 key_get_value "search " ${interfaces}) 31 set -- ${domain} 32 unset domain 33 if [ -n "$2" ]; then 34 search="$search $@" 35 elif [ -n "$1" ]; then 36 domain="domain $1\n" 37 fi 38 [ -n "$search" ] && search="search $(uniqify $search)\n" 39 40 # Build the nameserver list 41 srvs=$(cd "$resolv_conf_dir"; \ 42 key_get_value "nameserver " ${interfaces}) 43 for x in $(uniqify ${srvs}); do 44 servers="${servers}nameserver $x\n" 45 done 46 fi 47 header="$signature_base${header:+ $from }$header" 48 49 # Assemble resolv.conf using our head and tail files 50 [ -f "$cf" ] && rm -f "$cf" 51 [ -d "$resolv_conf_dir" ] || mkdir -p "$resolv_conf_dir" 52 echo "$header" > "$cf" 53 if [ -f /etc/resolv.conf.head ]; then 54 cat /etc/resolv.conf.head >> "$cf" 55 else 56 echo "# /etc/resolv.conf.head can replace this line" >> "$cf" 57 fi 58 printf "$domain$search$servers" >> "$cf" 59 if [ -f /etc/resolv.conf.tail ]; then 60 cat /etc/resolv.conf.tail >> "$cf" 61 else 62 echo "# /etc/resolv.conf.tail can replace this line" >> "$cf" 63 fi 64 cat "$cf" > /etc/resolv.conf 65 chmod 644 /etc/resolv.conf 66 rm -f "$cf" 67 } 68 69 add_resolv_conf() 70 { 71 local x= conf="$signature\n" 72 73 # If we don't have any configuration, remove it 74 if [ -z "$new_domain_name_servers" -a \ 75 -z "$new_domain_name" -a \ 76 -z "$new_domain_search" ]; then 77 remove_resolv_conf 78 return $? 79 fi 80 81 if [ -n "$new_domain_name" ]; then 82 set -- $new_domain_name 83 new_domain_name="$1" 84 conf="${conf}domain $new_domain_name\n" 85 # Support RFC violating search in domain 86 if [ -z "$new_domain_search" -a -n "$2" ]; then 87 new_domain_search="$@" 88 fi 89 fi 90 if [ -n "$new_domain_search" ]; then 91 conf="${conf}search $new_domain_search\n" 92 fi 93 for x in ${new_domain_name_servers}; do 94 conf="${conf}nameserver $x\n" 95 done 96 if type resolvconf >/dev/null 2>&1; then 97 [ -n "$metric" ] && export IF_METRIC="$metric" 98 printf "$conf" | resolvconf -a "$interface" 99 return $? 100 fi 101 102 if [ -e "$resolv_conf_dir/$interface" ]; then 103 rm -f "$resolv_conf_dir/$interface" 104 fi 105 [ -d "$resolv_conf_dir" ] || mkdir -p "$resolv_conf_dir" 106 printf "$conf" > "$resolv_conf_dir/$interface" 107 build_resolv_conf 108 } 109 110 remove_resolv_conf() 111 { 112 if type resolvconf >/dev/null 2>&1; then 113 resolvconf -d "$interface" -f 114 else 115 if [ -e "$resolv_conf_dir/$interface" ]; then 116 rm -f "$resolv_conf_dir/$interface" 117 fi 118 build_resolv_conf 119 fi 120 } 121 122 if $if_up; then 123 add_resolv_conf 124 elif $if_down; then 125 remove_resolv_conf 126 fi 127
