Mercurial > hg > dhcpcd
annotate hooks/20-resolv.conf @ 5535:a0d828e25482 draft
Add --noconfigure option
With this set dhcpcd will not configure anything on the host.
The expectation is that a 3rd party script will instead.
| author | Roy Marples <roy@marples.name> |
|---|---|
| date | Wed, 04 Nov 2020 14:18:48 +0000 |
| parents | b2ea9faab536 |
| children | 4fe5c2a71254 |
| rev | line source |
|---|---|
| 3936 | 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 NL=" | |
| 11 " | |
| 12 : ${resolvconf:=resolvconf} | |
| 13 | |
| 14 build_resolv_conf() | |
| 15 { | |
|
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16 cf="$state_dir/resolv.conf.$ifname" |
| 3936 | 17 |
| 18 # Build a list of interfaces | |
| 19 interfaces=$(list_interfaces "$resolv_conf_dir") | |
| 20 | |
| 21 # Build the resolv.conf | |
|
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22 header= |
| 3936 | 23 if [ -n "$interfaces" ]; then |
| 24 # Build the header | |
| 25 for x in ${interfaces}; do | |
| 26 header="$header${header:+, }$x" | |
| 27 done | |
| 28 | |
| 29 # Build the search list | |
| 30 domain=$(cd "$resolv_conf_dir"; \ | |
| 31 key_get_value "domain " ${interfaces}) | |
| 32 search=$(cd "$resolv_conf_dir"; \ | |
| 33 key_get_value "search " ${interfaces}) | |
| 34 set -- ${domain} | |
| 35 domain="$1" | |
| 36 [ -n "$2" ] && search="$search $*" | |
| 37 [ -n "$search" ] && search="$(uniqify $search)" | |
| 38 [ "$domain" = "$search" ] && search= | |
| 39 [ -n "$domain" ] && domain="domain $domain$NL" | |
| 40 [ -n "$search" ] && search="search $search$NL" | |
| 41 | |
| 42 # Build the nameserver list | |
| 43 srvs=$(cd "$resolv_conf_dir"; \ | |
| 44 key_get_value "nameserver " ${interfaces}) | |
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45 for x in $(uniqify $srvs); do |
| 3936 | 46 servers="${servers}nameserver $x$NL" |
| 47 done | |
| 48 fi | |
| 49 header="$signature_base${header:+ $from }$header" | |
| 50 | |
| 51 # Assemble resolv.conf using our head and tail files | |
| 52 [ -f "$cf" ] && rm -f "$cf" | |
| 53 [ -d "$resolv_conf_dir" ] || mkdir -p "$resolv_conf_dir" | |
| 54 echo "$header" > "$cf" | |
| 55 if [ -f /etc/resolv.conf.head ]; then | |
| 56 cat /etc/resolv.conf.head >> "$cf" | |
| 57 else | |
| 58 echo "# /etc/resolv.conf.head can replace this line" >> "$cf" | |
| 59 fi | |
| 60 printf %s "$domain$search$servers" >> "$cf" | |
| 61 if [ -f /etc/resolv.conf.tail ]; then | |
| 62 cat /etc/resolv.conf.tail >> "$cf" | |
| 63 else | |
| 64 echo "# /etc/resolv.conf.tail can replace this line" >> "$cf" | |
| 65 fi | |
| 66 if change_file /etc/resolv.conf "$cf"; then | |
| 67 chmod 644 /etc/resolv.conf | |
| 68 fi | |
| 69 rm -f "$cf" | |
| 70 } | |
| 71 | |
| 72 # Extract any ND DNS options from the RA | |
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73 # Obey the lifetimes |
| 3936 | 74 eval_nd_dns() |
| 75 { | |
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76 |
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77 eval rdnsstime=\$nd${i}_rdnss${j}_lifetime |
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78 [ -z "$rdnsstime" ] && return 1 |
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79 ltime=$(($rdnsstime - $offset)) |
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80 if [ "$ltime" -gt 0 ]; then |
| 3936 | 81 eval rdnss=\$nd${i}_rdnss${j}_servers |
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82 [ -n "$rdnss" ] && new_rdnss="$new_rdnss${new_rdnss:+ }$rdnss" |
| 3936 | 83 fi |
| 84 | |
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85 eval dnssltime=\$nd${i}_dnssl${j}_lifetime |
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86 [ -z "$dnssltime" ] && return 1 |
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parents:
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87 ltime=$(($dnssltime - $offset)) |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
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diff
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88 if [ "$ltime" -gt 0 ]; then |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
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diff
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89 eval dnssl=\$nd${i}_dnssl${j}_search |
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RA: expire RDNSS and DNSSL entries
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parents:
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diff
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90 [ -n "$dnssl" ] && new_dnssl="$new_dnssl${new_dnssl:+ }$dnssl" |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
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diff
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91 fi |
| 3936 | 92 |
| 93 j=$(($j + 1)) | |
| 94 return 0 | |
| 95 } | |
| 96 | |
| 97 add_resolv_conf() | |
| 98 { | |
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99 conf="$signature$NL" |
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e323d30f279e
dhcpcd-run-hooks: POSIX shell does not require the local builtin
Roy Marples <roy@marples.name>
parents:
3936
diff
changeset
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100 warn=true |
| 3936 | 101 |
| 102 # Loop to extract the ND DNS options using our indexed shell values | |
| 103 i=1 | |
| 104 j=1 | |
| 105 while true; do | |
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106 eval acquired=\$nd${i}_acquired |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
4322
diff
changeset
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107 [ -z "$acquired" ] && break |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
4322
diff
changeset
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108 eval now=\$nd${i}_now |
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999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
4322
diff
changeset
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109 [ -z "$now" ] && break |
|
999c0c21711d
RA: expire RDNSS and DNSSL entries
Roy Marples <roy@marples.name>
parents:
4322
diff
changeset
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110 offset=$(($now - $acquired)) |
| 3936 | 111 while true; do |
| 112 eval_nd_dns || break | |
| 113 done | |
| 114 i=$(($i + 1)) | |
| 115 j=1 | |
| 116 done | |
| 117 [ -n "$new_rdnss" ] && \ | |
| 118 new_domain_name_servers="$new_domain_name_servers${new_domain_name_servers:+ }$new_rdnss" | |
| 119 [ -n "$new_dnssl" ] && \ | |
| 120 new_domain_search="$new_domain_search${new_domain_search:+ }$new_dnssl" | |
| 121 | |
| 122 # Derive a new domain from our various hostname options | |
| 123 if [ -z "$new_domain_name" ]; then | |
| 124 if [ "$new_dhcp6_fqdn" != "${new_dhcp6_fqdn#*.}" ]; then | |
| 125 new_domain_name="${new_dhcp6_fqdn#*.}" | |
| 126 elif [ "$new_fqdn" != "${new_fqdn#*.}" ]; then | |
| 127 new_domain_name="${new_fqdn#*.}" | |
| 128 elif [ "$new_host_name" != "${new_host_name#*.}" ]; then | |
| 129 new_domain_name="${new_host_name#*.}" | |
| 130 fi | |
| 131 fi | |
| 132 | |
| 133 # If we don't have any configuration, remove it | |
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134 if [ -z "$new_domain_name_servers" ] && |
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0b2abe4e9d2e
hooks: shell [ ] only supports 4 parameters
Roy Marples <roy@marples.name>
parents:
4215
diff
changeset
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135 [ -z "$new_domain_name" ] && |
|
0b2abe4e9d2e
hooks: shell [ ] only supports 4 parameters
Roy Marples <roy@marples.name>
parents:
4215
diff
changeset
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136 [ -z "$new_domain_search" ]; then |
| 3936 | 137 remove_resolv_conf |
| 138 return $? | |
| 139 fi | |
| 140 | |
| 141 if [ -n "$new_domain_name" ]; then | |
| 142 set -- $new_domain_name | |
| 143 if valid_domainname "$1"; then | |
| 144 conf="${conf}domain $1$NL" | |
| 145 else | |
| 146 syslog err "Invalid domain name: $1" | |
| 147 fi | |
| 148 # If there is no search this, make this one | |
| 149 if [ -z "$new_domain_search" ]; then | |
| 150 new_domain_search="$new_domain_name" | |
| 151 [ "$new_domain_name" = "$1" ] && warn=true | |
| 152 fi | |
| 153 fi | |
| 154 if [ -n "$new_domain_search" ]; then | |
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parents:
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diff
changeset
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155 new_domain_search=$(uniqify $new_domain_search) |
| 3936 | 156 if valid_domainname_list $new_domain_search; then |
| 157 conf="${conf}search $new_domain_search$NL" | |
| 158 elif ! $warn; then | |
| 159 syslog err "Invalid domain name in list:" \ | |
| 160 "$new_domain_search" | |
| 161 fi | |
| 162 fi | |
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resolv.conf: Uniquify contents
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parents:
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diff
changeset
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163 new_domain_name_servers=$(uniqify $new_domain_name_servers) |
| 3936 | 164 for x in ${new_domain_name_servers}; do |
| 165 conf="${conf}nameserver $x$NL" | |
| 166 done | |
| 167 if type "$resolvconf" >/dev/null 2>&1; then | |
| 168 [ -n "$ifmetric" ] && export IF_METRIC="$ifmetric" | |
| 169 printf %s "$conf" | "$resolvconf" -a "$ifname" | |
| 170 return $? | |
| 171 fi | |
| 172 | |
| 173 if [ -e "$resolv_conf_dir/$ifname" ]; then | |
| 174 rm -f "$resolv_conf_dir/$ifname" | |
| 175 fi | |
| 176 [ -d "$resolv_conf_dir" ] || mkdir -p "$resolv_conf_dir" | |
| 177 printf %s "$conf" > "$resolv_conf_dir/$ifname" | |
| 178 build_resolv_conf | |
| 179 } | |
| 180 | |
| 181 remove_resolv_conf() | |
| 182 { | |
| 183 if type "$resolvconf" >/dev/null 2>&1; then | |
| 184 "$resolvconf" -d "$ifname" -f | |
| 185 else | |
| 186 if [ -e "$resolv_conf_dir/$ifname" ]; then | |
| 187 rm -f "$resolv_conf_dir/$ifname" | |
| 188 fi | |
| 189 build_resolv_conf | |
| 190 fi | |
| 191 } | |
| 192 | |
| 193 # For ease of use, map DHCP6 names onto our DHCP4 names | |
| 194 case "$reason" in | |
| 195 BOUND6|RENEW6|REBIND6|REBOOT6|INFORM6) | |
| 196 new_domain_name_servers="$new_dhcp6_name_servers" | |
| 197 new_domain_search="$new_dhcp6_domain_search" | |
| 198 ;; | |
| 199 esac | |
| 200 | |
| 5535 | 201 if $if_configured; then |
| 202 if $if_up || [ "$reason" = ROUTERADVERT ]; then | |
| 203 add_resolv_conf | |
| 204 elif $if_down; then | |
| 205 remove_resolv_conf | |
| 206 fi | |
| 3936 | 207 fi |