Merge pull request #4 from morphis/network-support

Add network support

android/anboxd.rc

 service anboxd /system/bin/anboxd
     class boot
+
+# We will ever only have a single network interface we need to care
+# about so we can add static setup for this one here.
+service anbox-network /system/bin/dhcptool eth0
+    class main
+    oneshot

scripts/anbox-bridge.sh

+#!/bin/sh
+# Copyright (C) 2016 The Linux Containers Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Taken from https://github.com/lxc/lxd-pkg-ubuntu/blob/dpm-xenial/lxd-bridge/lxd-bridge
+
+varrun="/run/anbox"
+varlib="/var/lib/anbox"
+
+BRIDGE="anboxbr0"
+
+# IPv4
+IPV4_ADDR="10.0.6.1"
+IPV4_NETMASK="255.255.255.0"
+IPV4_NETWORK="10.0.6.1/24"
+IPV4_DHCP_RANGE="10.0.6.2,10.0.6.254"
+IPV4_DHCP_MAX="252"
+IPV4_NAT="true"
+
+# IPv6
+IPV6_ADDR="fd9d:e4dc:4e00:9e98::1"
+IPV6_MASK="64"
+IPV6_NETWORK="fd9d:e4dc:4e00:9e98::1/64"
+IPV6_NAT="true"
+IPV6_PROXY="false"
+
+use_iptables_lock="-w"
+iptables -w -L -n > /dev/null 2>&1 || use_iptables_lock=""
+
+HAS_IPV6=false
+[ -e "/proc/sys/net/ipv6/conf/default/disable_ipv6" ] && \
+    [ "$(cat /proc/sys/net/ipv6/conf/default/disable_ipv6)" = "0" ] && HAS_IPV6=true
+
+_netmask2cidr () {
+    # Assumes there's no "255." after a non-255 byte in the mask
+    local x=${1##*255.}
+    set -- "0^^^128^192^224^240^248^252^254^" "$(( (${#1} - ${#x})*2 ))" "${x%%.*}"
+    x=${1%%${3}*}
+    echo $(( ${2} + (${#x}/4) ))
+}
+
+ifdown() {
+    ip addr flush dev "${1}"
+    ip link set dev "${1}" down
+}
+
+ifup() {
+    [ "${HAS_IPV6}" = "true" ] && [ "${IPV6_PROXY}" = "true" ] && ip addr add fe80::1/64 dev "${1}"
+    if [ -n "${IPV4_NETMASK}" ] && [ -n "${IPV4_ADDR}" ]; then
+        MASK=$(_netmask2cidr ${IPV4_NETMASK})
+        CIDR_ADDR="${IPV4_ADDR}/${MASK}"
+        ip addr add "${CIDR_ADDR}" dev "${1}"
+    fi
+    ip link set dev "${1}" up
+}
+
+start() {
+    [ ! -f "${varrun}/network_up" ] || { echo "anbox-bridge is already running"; exit 1; }
+
+    if [ -d /sys/class/net/${BRIDGE} ]; then
+        stop force 2>/dev/null || true
+    fi
+
+    FAILED=1
+
+    cleanup() {
+        set +e
+        if [ "${FAILED}" = "1" ]; then
+            echo "Failed to setup anbox-bridge." >&2
+            stop force
+        fi
+    }
+
+    trap cleanup EXIT HUP INT TERM
+    set -e
+
+    # set up the anbox network
+    [ ! -d "/sys/class/net/${BRIDGE}" ] && ip link add dev "${BRIDGE}" type bridge
+
+    if [ "${HAS_IPV6}" = "true" ]; then
+        echo 0 > "/proc/sys/net/ipv6/conf/${BRIDGE}/autoconf" || true
+        echo 0 > "/proc/sys/net/ipv6/conf/${BRIDGE}/accept_dad" || true
+    fi
+
+    # if we are run from systemd on a system with selinux enabled,
+    # the mkdir will create /run/anbox as init_var_run_t which dnsmasq
+    # can't write its pid into, so we restorecon it (to var_run_t)
+    if [ ! -d "${varrun}" ]; then
+        mkdir -p "${varrun}"
+        if which restorecon >/dev/null 2>&1; then
+            restorecon "${varrun}"
+        fi
+    fi
+
+    if [ ! -d "${varlib}" ]; then
+        mkdir -p "${varlib}"
+        if which restorecon >/dev/null 2>&1; then
+            restorecon "${varlib}"
+        fi
+    fi
+
+    ifup "${BRIDGE}" "${IPV4_ADDR}" "${IPV4_NETMASK}"
+
+    IPV4_ARG=""
+    if [ -n "${IPV4_ADDR}" ] && [ -n "${IPV4_NETMASK}" ] && [ -n "${IPV4_NETWORK}" ]; then
+        echo 1 > /proc/sys/net/ipv4/ip_forward
+        if [ "${IPV4_NAT}" = "true" ]; then
+            iptables "${use_iptables_lock}" -t nat -A POSTROUTING -s "${IPV4_NETWORK}" ! -d "${IPV4_NETWORK}" -j MASQUERADE -m comment --comment "managed by anbox-bridge"
+        fi
+        IPV4_ARG="--listen-address ${IPV4_ADDR} --dhcp-range ${IPV4_DHCP_RANGE} --dhcp-lease-max=${IPV4_DHCP_MAX}"
+    fi
+
+    IPV6_ARG=""
+    if [ "${HAS_IPV6}" = "true" ] && [ -n "${IPV6_ADDR}" ] && [ -n "${IPV6_MASK}" ] && [ -n "${IPV6_NETWORK}" ]; then
+        # IPv6 sysctls don't respect the "all" path...
+        for interface in /proc/sys/net/ipv6/conf/*; do
+            echo 2 > "${interface}/accept_ra"
+        done
+
+        for interface in /proc/sys/net/ipv6/conf/*; do
+            echo 1 > "${interface}/forwarding"
+        done
+
+        ip -6 addr add dev "${BRIDGE}" "${IPV6_ADDR}/${IPV6_MASK}"
+        if [ "${IPV6_NAT}" = "true" ]; then
+            ip6tables "${use_iptables_lock}" -t nat -A POSTROUTING -s "${IPV6_NETWORK}" ! -d "${IPV6_NETWORK}" -j MASQUERADE -m comment --comment "managed by anbox-bridge"
+        fi
+        IPV6_ARG="--dhcp-range=${IPV6_ADDR},ra-stateless,ra-names --listen-address ${IPV6_ADDR}"
+    fi
+
+    iptables "${use_iptables_lock}" -I INPUT -i "${BRIDGE}" -p udp --dport 67 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -I INPUT -i "${BRIDGE}" -p tcp --dport 67 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -I INPUT -i "${BRIDGE}" -p udp --dport 53 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -I INPUT -i "${BRIDGE}" -p tcp --dport 53 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -I FORWARD -i "${BRIDGE}" -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -I FORWARD -o "${BRIDGE}" -j ACCEPT -m comment --comment "managed by anbox-bridge"
+    iptables "${use_iptables_lock}" -t mangle -A POSTROUTING -o "${BRIDGE}" -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill -m comment --comment "managed by anbox-bridge"
+
+    DOMAIN_ARG=""
+    if [ -n "${DOMAIN}" ]; then
+        DOMAIN_ARG="-s ${DOMAIN} -S /${DOMAIN}/"
+    fi
+
+    CONFILE_ARG=""
+    if [ -n "${CONFILE}" ]; then
+        CONFILE_ARG="--conf-file=${CONFILE}"
+    fi
+
+    # https://lists.linuxcontainers.org/pipermail/lxc-devel/2014-October/010561.html
+    for DNSMASQ_USER in anbox dnsmasq nobody
+    do
+        if getent passwd "${DNSMASQ_USER}" >/dev/null; then
+            break
+        fi
+    done
+
+    if [ -n "${IPV4_ADDR}" ] || [ -n "${IPV6_ADDR}" ]; then
+        # shellcheck disable=SC2086
+        dnsmasq ${CONFILE_ARG} ${DOMAIN_ARG} -u "${DNSMASQ_USER}" --strict-order --bind-interfaces --pid-file="${varrun}/dnsmasq.pid" --dhcp-no-override --except-interface=lo --interface="${BRIDGE}" --dhcp-leasefile="${varlib}/dnsmasq.${BRIDGE}.leases" --dhcp-authoritative ${IPV4_ARG} ${IPV6_ARG} || cleanup
+    fi
+
+    if [ "${HAS_IPV6}" = "true" ] && [ "${IPV6_PROXY}" = "true" ]; then
+        PATH="${PATH}:$(dirname "${0}")" anbox-bridge-proxy --addr="[fe80::1%${BRIDGE}]:13128" &
+        PID=$!
+        echo "${PID}" > "${varrun}/proxy.pid"
+    fi
+
+    touch "${varrun}/network_up"
+    FAILED=0
+}
+
+stop() {
+    [ -f "${varrun}/network_up" ] || [ "${1}" = "force" ] || { echo "anbox-bridge isn't running"; exit 1; }
+
+    if [ -d /sys/class/net/${BRIDGE} ]; then
+        ifdown ${BRIDGE}
+        iptables ${use_iptables_lock} -D INPUT -i ${BRIDGE} -p udp --dport 67 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -D INPUT -i ${BRIDGE} -p tcp --dport 67 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -D INPUT -i ${BRIDGE} -p udp --dport 53 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -D INPUT -i ${BRIDGE} -p tcp --dport 53 -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -D FORWARD -i ${BRIDGE} -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -D FORWARD -o ${BRIDGE} -j ACCEPT -m comment --comment "managed by anbox-bridge"
+        iptables ${use_iptables_lock} -t mangle -D POSTROUTING -o ${BRIDGE} -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill -m comment --comment "managed by anbox-bridge"
+
+        if [ -n "${IPV4_NETWORK}" ] && [ "${IPV4_NAT}" = "true" ]; then
+            iptables ${use_iptables_lock} -t nat -D POSTROUTING -s ${IPV4_NETWORK} ! -d ${IPV4_NETWORK} -j MASQUERADE -m comment --comment "managed by anbox-bridge"
+        fi
+
+        if [ "${HAS_IPV6}" = "true" ] && [ -n "${IPV6_NETWORK}" ] && [ "${IPV6_NAT}" = "true" ]; then
+            ip6tables ${use_iptables_lock} -t nat -D POSTROUTING -s ${IPV6_NETWORK} ! -d ${IPV6_NETWORK} -j MASQUERADE -m comment --comment "managed by anbox-bridge"
+        fi
+
+        if [ -e "${varrun}/dnsmasq.pid" ]; then
+            pid=$(cat "${varrun}/dnsmasq.pid" 2>/dev/null) && kill -9 "${pid}"
+            rm -f "${varrun}/dnsmasq.pid"
+        fi
+
+        if [ -e "${varrun}/proxy.pid" ]; then
+            pid=$(cat "${varrun}/proxy.pid" 2>/dev/null) && kill -9 "${pid}"
+            rm -f "${varrun}/proxy.pid"
+        fi
+
+        # if ${BRIDGE} has attached interfaces, don't destroy the bridge
+        ls /sys/class/net/${BRIDGE}/brif/* > /dev/null 2>&1 || ip link delete "${BRIDGE}"
+    fi
+
+    rm -f "${varrun}/network_up"
+}
+
+# See how we were called.
+case "${1}" in
+    start)
+        start
+    ;;
+
+    stop)
+        stop
+    ;;
+
+    restart|reload|force-reload)
+        ${0} stop
+        ${0} start
+    ;;
+
+    *)
+        echo "Usage: ${0} {start|stop|restart|reload|force-reload}"
+        exit 2
+esac
+
+exit $?

snapcraft.yaml

@@ -16,6 +16,10 @@ apps:
     daemon: simple
   shell:
     command: bin/container-shell.sh
+  bridge:
+    command: bin/anbox-bridge.sh start
+    stop-command: bin/anbox-bridge.sh stop
+    daemon: oneshot
 
 parts:
   android-rootfs:
@@ -29,8 +33,9 @@ parts:
     files:
       scripts/snap-wrapper.sh: bin/anbox-wrapper.sh
       scripts/container-manager.sh: bin/container-manager.sh
-      scripts/container-shell.sh: bin/container-shell.sh
+      scripts/anbox-bridge.sh: bin/anbox-bridge.sh
     snap:
+      - bin/anbox-bridge.sh
       - bin/anbox-wrapper.sh
       - bin/container-manager.sh
       - bin/container-shell.sh

src/anbox/container/lxc_container.cpp

@@ -106,6 +106,10 @@ void LxcContainer::start(const Configuration &configuration) {
     set_config_item("lxc.loglevel", "0");
     set_config_item("lxc.logfile", utils::string_format("%s/container.log", config::log_path()).c_str());
 
+    set_config_item("lxc.network.type", "veth");
+    set_config_item("lxc.network.flags", "up");
+    set_config_item("lxc.network.link", "anboxbr0");
+
 #if 0
     // Android uses namespaces as well so we have to allow nested namespaces for LXC
     // which are otherwise forbidden by AppArmor.