data/scripts/waydroid-net.sh

   1 #!/bin/sh -
   2
   3 varrun="/run/waydroid-lxc"
   4 varlib="/var/lib"
   5 vnic=$(awk '$1 == "lxc.net.0.link" {print $3}' /var/lib/waydroid/lxc/waydroid/config || echo "waydroid0")
   6
   7 if [ "$vnic" != "waydroid0" ]; then
   8     echo "vnic is $vnic, bailing out"
   9     exit 0
  10 else
  11     echo "vnic is waydroid0"
  12 fi
  13
  14 USE_LXC_BRIDGE="true"
  15 LXC_BRIDGE="${vnic}"
  16 LXC_BRIDGE_MAC="00:16:3e:00:00:01"
  17 LXC_ADDR="192.168.240.1"
  18 LXC_NETMASK="255.255.255.0"
  19 LXC_NETWORK="192.168.240.0/24"
  20 LXC_DHCP_RANGE="192.168.240.2,192.168.240.254"
  21 LXC_DHCP_MAX="253"
  22 LXC_DHCP_CONFILE=""
  23 LXC_DHCP_PING="true"
  24 LXC_DOMAIN=""
  25 LXC_USE_NFT="false"
  26
  27 LXC_IPV6_ADDR=""
  28 LXC_IPV6_MASK=""
  29 LXC_IPV6_NETWORK=""
  30 LXC_IPV6_NAT="false"
  31
  32 IPTABLES_BIN="$(which iptables-legacy)"
  33 if [ ! -n "$IPTABLES_BIN" ]; then
  34     IPTABLES_BIN="$(which iptables)"
  35 fi
  36 IP6TABLES_BIN="$(which ip6tables-legacy)"
  37 if [ ! -n "$IP6TABLES_BIN" ]; then
  38     IP6TABLES_BIN="$(which ip6tables)"
  39 fi
  40
  41 use_nft() {
  42     [ -n "$NFT" ] && nft list ruleset > /dev/null 2>&1 && [ "$LXC_USE_NFT" = "true" ]
  43 }
  44
  45 NFT="$(which nft)"
  46 if ! use_nft; then
  47     use_iptables_lock="-w"
  48     $IPTABLES_BIN -w -L -n > /dev/null 2>&1 || use_iptables_lock=""
  49 fi
  50
  51 _netmask2cidr ()
  52 {
  53     # Assumes there's no "255." after a non-255 byte in the mask
  54     local x=${1##*255.}
  55     set -- 0^^^128^192^224^240^248^252^254^ $(( (${#1} - ${#x})*2 )) ${x%%.*}
  56     x=${1%%$3*}
  57     echo $(( $2 + (${#x}/4) ))
  58 }
  59
  60 _ifdown() {
  61     ip addr flush dev ${LXC_BRIDGE}
  62     ip link set dev ${LXC_BRIDGE} down
  63 }
  64
  65 _ifup() {
  66     MASK=`_netmask2cidr ${LXC_NETMASK}`
  67     CIDR_ADDR="${LXC_ADDR}/${MASK}"
  68     ip addr add ${CIDR_ADDR} broadcast + dev ${LXC_BRIDGE}
  69     ip link set dev ${LXC_BRIDGE} address $LXC_BRIDGE_MAC
  70     ip link set dev ${LXC_BRIDGE} up
  71 }
  72
  73 start_ipv6() {
  74     LXC_IPV6_ARG=""
  75     if [ -n "$LXC_IPV6_ADDR" ] && [ -n "$LXC_IPV6_MASK" ] && [ -n "$LXC_IPV6_NETWORK" ]; then
  76         echo 1 > /proc/sys/net/ipv6/conf/all/forwarding
  77         echo 0 > /proc/sys/net/ipv6/conf/${LXC_BRIDGE}/autoconf
  78         ip -6 addr add dev ${LXC_BRIDGE} ${LXC_IPV6_ADDR}/${LXC_IPV6_MASK}
  79         LXC_IPV6_ARG="--dhcp-range=${LXC_IPV6_ADDR},ra-only --listen-address ${LXC_IPV6_ADDR}"
  80     fi
  81 }
  82
  83 start_iptables() {
  84     start_ipv6
  85     if [ -n "$LXC_IPV6_ARG" ] && [ "$LXC_IPV6_NAT" = "true" ]; then
  86         $IP6TABLES_BIN $use_iptables_lock -t nat -A POSTROUTING -s ${LXC_IPV6_NETWORK} ! -d ${LXC_IPV6_NETWORK} -j MASQUERADE
  87     fi
  88     $IPTABLES_BIN $use_iptables_lock -I INPUT -i ${LXC_BRIDGE} -p udp --dport 67 -j ACCEPT
  89     $IPTABLES_BIN $use_iptables_lock -I INPUT -i ${LXC_BRIDGE} -p tcp --dport 67 -j ACCEPT
  90     $IPTABLES_BIN $use_iptables_lock -I INPUT -i ${LXC_BRIDGE} -p udp --dport 53 -j ACCEPT
  91     $IPTABLES_BIN $use_iptables_lock -I INPUT -i ${LXC_BRIDGE} -p tcp --dport 53 -j ACCEPT
  92     $IPTABLES_BIN $use_iptables_lock -I FORWARD -i ${LXC_BRIDGE} -j ACCEPT
  93     $IPTABLES_BIN $use_iptables_lock -I FORWARD -o ${LXC_BRIDGE} -j ACCEPT
  94     $IPTABLES_BIN $use_iptables_lock -t nat -A POSTROUTING -s ${LXC_NETWORK} ! -d ${LXC_NETWORK} -j MASQUERADE
  95     $IPTABLES_BIN $use_iptables_lock -t mangle -A POSTROUTING -o ${LXC_BRIDGE} -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill
  96 }
  97
  98 start_nftables() {
  99     start_ipv6
 100     NFT_RULESET=""
 101     if [ -n "$LXC_IPV6_ARG" ] && [ "$LXC_IPV6_NAT" = "true" ]; then
 102         NFT_RULESET="${NFT_RULESET}
 103 add table ip6 lxc;
 104 flush table ip6 lxc;
 105 add chain ip6 lxc postrouting { type nat hook postrouting priority 100; };
 106 add rule ip6 lxc postrouting ip saddr ${LXC_IPV6_NETWORK} ip daddr != ${LXC_IPV6_NETWORK} counter masquerade;
 107 "
 108     fi
 109     NFT_RULESET="${NFT_RULESET};
 110 add table inet lxc;
 111 flush table inet lxc;
 112 add chain inet lxc input { type filter hook input priority 0; };
 113 add rule inet lxc input iifname ${LXC_BRIDGE} udp dport { 53, 67 } accept;
 114 add rule inet lxc input iifname ${LXC_BRIDGE} tcp dport { 53, 67 } accept;
 115 add chain inet lxc forward { type filter hook forward priority 0; };
 116 add rule inet lxc forward iifname ${LXC_BRIDGE} accept;
 117 add rule inet lxc forward oifname ${LXC_BRIDGE} accept;
 118 add table ip lxc;
 119 flush table ip lxc;
 120 add chain ip lxc postrouting { type nat hook postrouting priority 100; };
 121 add rule ip lxc postrouting ip saddr ${LXC_NETWORK} ip daddr != ${LXC_NETWORK} counter masquerade"
 122     nft "${NFT_RULESET}"
 123 }
 124
 125 start() {
 126     [ "x$USE_LXC_BRIDGE" = "xtrue" ] || { exit 0; }
 127
 128     [ ! -f "${varrun}/network_up" ] || { echo "waydroid-net is already running"; exit 1; }
 129
 130     if [ -d /sys/class/net/${LXC_BRIDGE} ]; then
 131         stop force || true
 132     fi
 133
 134     FAILED=1
 135
 136     cleanup() {
 137         set +e
 138         if [ "$FAILED" = "1" ]; then
 139             echo "Failed to setup waydroid-net." >&2
 140             stop force
 141             exit 1
 142         fi
 143     }
 144
 145     trap cleanup EXIT HUP INT TERM
 146     set -e
 147
 148     # set up the lxc network
 149     [ ! -d /sys/class/net/${LXC_BRIDGE} ] && ip link add dev ${LXC_BRIDGE} type bridge
 150     echo 1 > /proc/sys/net/ipv4/ip_forward
 151     echo 0 > /proc/sys/net/ipv6/conf/${LXC_BRIDGE}/accept_dad || true
 152
 153     # if we are run from systemd on a system with selinux enabled,
 154     # the mkdir will create /run/lxc as init_var_run_t which dnsmasq
 155     # can't write its pid into, so we restorecon it (to var_run_t)
 156     if [ ! -d "${varrun}" ]; then
 157         mkdir -p "${varrun}"
 158         if which restorecon >/dev/null 2>&1; then
 159             restorecon "${varrun}"
 160         fi
 161     fi
 162
 163     _ifup
 164
 165     if use_nft; then
 166         start_nftables
 167     else
 168         start_iptables
 169     fi
 170
 171     LXC_DOMAIN_ARG=""
 172     if [ -n "$LXC_DOMAIN" ]; then
 173         LXC_DOMAIN_ARG="-s $LXC_DOMAIN -S /$LXC_DOMAIN/"
 174     fi
 175
 176     # lxc's dnsmasq should be hermetic and not read `/etc/dnsmasq.conf` (which
 177     # it does by default if `--conf-file` is not present
 178     LXC_DHCP_CONFILE_ARG="--conf-file=${LXC_DHCP_CONFILE:-/dev/null}"
 179
 180     # https://lists.linuxcontainers.org/pipermail/lxc-devel/2014-October/010561.html
 181     for DNSMASQ_USER in lxc-dnsmasq dnsmasq nobody
 182     do
 183         if getent passwd ${DNSMASQ_USER} >/dev/null; then
 184             break
 185         fi
 186     done
 187
 188     LXC_DHCP_PING_ARG=""
 189     if [ "x$LXC_DHCP_PING" = "xfalse" ]; then
 190         LXC_DHCP_PING_ARG="--no-ping"
 191     fi
 192
 193     if [ ! -d "${varlib}"/misc ]; then
 194         mkdir "${varlib}"/misc
 195     fi
 196
 197     dnsmasq $LXC_DHCP_CONFILE_ARG $LXC_DOMAIN_ARG $LXC_DHCP_PING_ARG -u ${DNSMASQ_USER} \
 198             --strict-order --bind-interfaces --pid-file="${varrun}"/dnsmasq.pid \
 199             --listen-address ${LXC_ADDR} --dhcp-range ${LXC_DHCP_RANGE} \
 200             --dhcp-lease-max=${LXC_DHCP_MAX} --dhcp-no-override \
 201             --except-interface=lo --interface=${LXC_BRIDGE} \
 202             --dhcp-leasefile="${varlib}"/misc/dnsmasq.${LXC_BRIDGE}.leases \
 203             --dhcp-authoritative $LXC_IPV6_ARG || cleanup
 204
 205     touch "${varrun}"/network_up
 206     FAILED=0
 207 }
 208
 209 stop_iptables() {
 210     $IPTABLES_BIN $use_iptables_lock -D INPUT -i ${LXC_BRIDGE} -p udp --dport 67 -j ACCEPT
 211     $IPTABLES_BIN $use_iptables_lock -D INPUT -i ${LXC_BRIDGE} -p tcp --dport 67 -j ACCEPT
 212     $IPTABLES_BIN $use_iptables_lock -D INPUT -i ${LXC_BRIDGE} -p udp --dport 53 -j ACCEPT
 213     $IPTABLES_BIN $use_iptables_lock -D INPUT -i ${LXC_BRIDGE} -p tcp --dport 53 -j ACCEPT
 214     $IPTABLES_BIN $use_iptables_lock -D FORWARD -i ${LXC_BRIDGE} -j ACCEPT
 215     $IPTABLES_BIN $use_iptables_lock -D FORWARD -o ${LXC_BRIDGE} -j ACCEPT
 216     $IPTABLES_BIN $use_iptables_lock -t nat -D POSTROUTING -s ${LXC_NETWORK} ! -d ${LXC_NETWORK} -j MASQUERADE
 217     $IPTABLES_BIN $use_iptables_lock -t mangle -D POSTROUTING -o ${LXC_BRIDGE} -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill
 218     if [ "$LXC_IPV6_NAT" = "true" ]; then
 219         $IP6TABLES_BIN $use_iptables_lock -t nat -D POSTROUTING -s ${LXC_IPV6_NETWORK} ! -d ${LXC_IPV6_NETWORK} -j MASQUERADE
 220     fi
 221 }
 222
 223 stop_nftables() {
 224     # Adding table before removing them is just to avoid
 225     # delete error for non-existent table
 226     NFT_RULESET="add table inet lxc;
 227 delete table inet lxc;
 228 add table ip lxc;
 229 delete table ip lxc;
 230 "
 231     if [ "$LXC_IPV6_NAT" = "true" ]; then
 232         NFT_RULESET="${NFT_RULESET};
 233 add table ip6 lxc;
 234 delete table ip6 lxc;"
 235     fi
 236     nft "${NFT_RULESET}"
 237 }
 238
 239 stop() {
 240     [ "x$USE_LXC_BRIDGE" = "xtrue" ] || { exit 0; }
 241
 242     [ -f "${varrun}/network_up" ] || [ "$1" = "force" ] || { echo "waydroid-net isn't running"; exit 1; }
 243
 244     if [ -d /sys/class/net/${LXC_BRIDGE} ]; then
 245         _ifdown
 246         if use_nft; then
 247             stop_nftables
 248         else
 249             stop_iptables
 250         fi
 251
 252         pid=`cat "${varrun}"/dnsmasq.pid 2>/dev/null` && kill -9 $pid
 253         rm -f "${varrun}"/dnsmasq.pid
 254         # if $LXC_BRIDGE has attached interfaces, don't destroy the bridge
 255         ls /sys/class/net/${LXC_BRIDGE}/brif/* > /dev/null 2>&1 || ip link delete ${LXC_BRIDGE}
 256     fi
 257
 258     rm -f "${varrun}"/network_up
 259 }
 260
 261 # See how we were called.
 262 case "$1" in
 263     start)
 264         start
 265     ;;
 266
 267     stop)
 268         stop
 269     ;;
 270
 271     restart|reload|force-reload)
 272         $0 stop
 273         $0 start
 274     ;;
 275
 276     *)
 277         echo "Usage: $0 {start|stop|restart|reload|force-reload}"
 278         exit 2
 279 esac
 280
 281 exit $?