scripts/qemustart

   1 #!/usr/bin/env bash
   2
   3 SELF="$0"
   4
   5 # Linux bridge for connecting lan and wan network of guest machines
   6 BR_LAN="${BR_LAN:-br-lan}"
   7 BR_WAN="${BR_WAN:-br-wan}"
   8
   9 # Host network interface providing internet access for guest machines
  10 IF_INET="${IF_INET:-eth0}"
  11
  12 # qemu-bridge-helper does two things here
  13 #
  14 # - create tap interface
  15 # - add the tap interface to bridge
  16 #
  17 # as such it requires CAP_NET_ADMIN to do its job.  It will be convenient to
  18 # have it as a root setuid program.  Be aware of the security risks implied
  19 #
  20 # the helper has an acl list which defaults to deny all bridge.  we need to add
  21 # $BR_LAN and $BR_WAN to its allow list
  22 #
  23 #       # sudo vim /etc/qemu/bridge.conf
  24 #       allow br-lan
  25 #       allow br-wan
  26 #
  27 # Other allowed directives can be 'allow all', 'deny all', 'include xxx',  See
  28 # qemu-bridge-helper.c of qemu source code for details.
  29 #
  30 # The helper can be provided by package qemu-system-common on debian, or
  31 # qemu-kvm-common on rhel
  32 #
  33 HELPER="${HELPER:-/usr/libexec/qemu-bridge-helper}"
  34
  35 ### end of global settings
  36
  37 __errmsg() {
  38         echo "$*" >&2
  39 }
  40
  41 do_setup() {
  42         # setup bridge for LAN network
  43         sudo ip link add dev "$BR_LAN" type bridge
  44         sudo ip link set dev "$BR_LAN" up
  45         sudo ip addr add 192.168.1.3/24 dev "$BR_LAN"
  46
  47         # setup bridge for WAN network
  48         #
  49         # minimal dnsmasq config for configuring guest wan network with dhcp
  50         #
  51         #       # sudo apt-get install dnsmasq
  52         #       # sudo vi /etc/dnsmasq.conf
  53         #       interface=br-wan
  54         #       dhcp-range=192.168.7.50,192.168.7.150,255.255.255.0,30m
  55         #
  56         sudo ip link add dev "$BR_WAN" type bridge
  57         sudo ip link set dev "$BR_WAN" up
  58         sudo ip addr add 192.168.7.1/24 dev "$BR_WAN"
  59
  60         # guest internet access
  61         sudo sysctl -w "net.ipv4.ip_forward=1"
  62         sudo sysctl -w "net.ipv4.conf.$BR_WAN.proxy_arp=1"
  63         while sudo iptables -t nat -D POSTROUTING -o "$IF_INET" -j MASQUERADE 2>/dev/null; do true; done
  64               sudo iptables -t nat -A POSTROUTING -o "$IF_INET" -j MASQUERADE
  65 }
  66
  67 check_setup_() {
  68         ip link show "$BR_LAN" >/dev/null || return 1
  69         ip link show "$BR_WAN" >/dev/null || return 1
  70         [ -x "$HELPER" ] || {
  71                 __errmsg "helper $HELPER is not an executable"
  72                 return 1
  73         }
  74 }
  75
  76 check_setup() {
  77         [ -z $o_nonetwork ] || return 0
  78         check_setup_ || {
  79                 __errmsg "please check the script content to see the environment requirement"
  80                 return 1
  81         }
  82 }
  83 #do_setup; check_setup; exit $?
  84
  85 usage() {
  86         cat >&2 <<EOF
  87 Usage: $SELF [-h|--help]
  88        $SELF <target>
  89          [<subtarget> [<extra-qemu-options>]]
  90          [--kernel <kernel>]
  91          [--rootfs <rootfs>]
  92          [--machine <machine>]
  93
  94 <subtarget> will default to "generic" and must be specified if
  95 <extra-qemu-options> are present
  96
  97 e.g. <subtarget> for malta can be le, be, le64, be64, le-glibc, le64-glibc, etc
  98
  99 <kernel>, <rootfs> can be required or optional arguments to qemu depending on
 100 the actual <target> in use.  They will default to files under bin/targets/
 101
 102 Examples
 103
 104   $SELF x86 64
 105   $SELF x86 64 --machine q35,accel=kvm -device virtio-balloon-pci
 106   $SELF x86 64 -incoming tcp:0:4444
 107   $SELF x86 64-glibc
 108   $SELF malta be -m 64
 109   $SELF malta le64
 110   $SELF malta be-glibc
 111   $SELF armvirt 32 \\
 112                 --machine virt,highmem=off \\
 113                 --kernel bin/targets/armvirt/32/openwrt-armvirt-32-zImage \\
 114                 --rootfs bin/targets/armvirt/32/openwrt-armvirt-32-root.ext4
 115 EOF
 116 }
 117
 118 rand_mac() {
 119         hexdump -n 3 -e '"52:54:00" 3/1 ":%02x"' /dev/urandom
 120 }
 121
 122 parse_args() {
 123         o_qemu_extra=()
 124         while [ "$#" -gt 0 ]; do
 125                 case "$1" in
 126                         --no-network|-n) o_nonetwork=1; shift ;;
 127                         --kernel) o_kernel="$2"; shift 2 ;;
 128                         --rootfs) o_rootfs="$2"; shift 2 ;;
 129                         --machine|-machine|-M) o_mach="$2"; shift 2 ;;
 130                         --help|-h)
 131                                 usage
 132                                 exit 0
 133                                 ;;
 134                         *)
 135                                 if [ -z "$o_target" ]; then
 136                                         o_target="$1"
 137                                 elif [ -z "$o_subtarget" ]; then
 138                                         o_subtarget="$1"
 139                                 else
 140                                         o_qemu_extra+=("$1")
 141                                 fi
 142                                 shift
 143                                 ;;
 144                 esac
 145         done
 146
 147         MAC_LAN="$(rand_mac)"
 148         MAC_WAN="$(rand_mac)"
 149         [ -n "$o_target" ] || {
 150                 usage
 151                 return 1
 152         }
 153         [ -n "$o_subtarget" ] || o_subtarget="generic"
 154         o_bindir="bin/targets/$o_target/$o_subtarget"
 155 }
 156
 157 start_qemu_armvirt() {
 158         local kernel="$o_kernel"
 159         local rootfs="$o_rootfs"
 160         local mach="${o_mach:-virt}"
 161         local cpu
 162         local qemu_exe
 163
 164         case "${o_subtarget%-*}" in
 165                 32)
 166                         qemu_exe="qemu-system-arm"
 167                         cpu="cortex-a15"
 168                         [ -n "$kernel" ] || kernel="$o_bindir/openwrt-$o_target-${o_subtarget%-*}-zImage-initramfs"
 169                         ;;
 170                 64)
 171                         qemu_exe="qemu-system-aarch64"
 172                         cpu="cortex-a57"
 173                         [ -n "$kernel" ] || kernel="$o_bindir/openwrt-$o_target-${o_subtarget%-*}-Image-initramfs"
 174                         ;;
 175                 *)
 176                         __errmsg "target $o_target: unknown subtarget $o_subtarget"
 177                         return 1
 178                         ;;
 179         esac
 180         [ -z "$rootfs" ] || {
 181                 if [ ! -f "$rootfs" -a -s "$rootfs.gz" ]; then
 182                         gunzip "$rootfs.gz"
 183                 fi
 184                 o_qemu_extra+=( \
 185                         "-drive" "file=$rootfs,format=raw,if=virtio" \
 186                         "-append" "root=/dev/vda rootwait" \
 187                 )
 188         }
 189
 190         [ -n $o_nonetwork ] || {
 191                 o_qemu_extra+=( \
 192                         "-netdev" "bridge,id=lan,br=$BR_LAN,helper=$HELPER" \
 193                             "-device" "virtio-net-pci,id=devlan,netdev=lan,mac=$MAC_LAN" \
 194                         "-netdev" "bridge,id=wan,br=$BR_WAN,helper=$HELPER" "-device" \
 195                             "virtio-net-pci,id=devwan,netdev=wan,mac=$MAC_WAN" \
 196                 )
 197         }
 198
 199         "$qemu_exe" -machine "$mach" -cpu "$cpu" -nographic \
 200                 -kernel "$kernel" \
 201                 "${o_qemu_extra[@]}"
 202 }
 203
 204 start_qemu_malta() {
 205         local is64
 206         local isel
 207         local qemu_exe
 208         local kernel="$o_kernel"
 209         local mach="${o_mach:-malta}"
 210
 211         # o_subtarget can be le, be, le64, be64, le-glibc, le64-glibc, etc..
 212         is64="$(echo $o_subtarget | grep -o 64)"
 213         [ "$(echo "$o_subtarget" | grep -o '^..')" = "le" ] && isel="el"
 214         qemu_exe="qemu-system-mips$is64$isel"
 215
 216         [ -n "$kernel" ] || kernel="$o_bindir/openwrt-malta-${o_subtarget%-*}-vmlinux-initramfs.elf"
 217
 218         # NOTE: order of wan, lan -device arguments matters as it will affect which
 219         # one will be actually used as the wan, lan network interface inside the
 220         # guest machine
 221         [ -n $o_nonetwork ] || {
 222                 o_qemu_extra+=( \
 223                         "-netdev" "bridge,id=wan,br=$BR_WAN,helper=$HELPER" "-device" \
 224                             "virtio-net-pci,id=devwan,netdev=wan,mac=$MAC_WAN" \
 225                         "-netdev" "bridge,id=lan,br=$BR_LAN,helper=$HELPER" \
 226                             "-device" "virtio-net-pci,id=devlan,netdev=lan,mac=$MAC_LAN" \
 227                 )
 228         }
 229
 230         "$qemu_exe" -machine "$mach" -nographic \
 231                 -kernel "$kernel" \
 232                 "${o_qemu_extra[@]}"
 233 }
 234
 235 start_qemu_x86() {
 236         local rootfs="$o_rootfs"
 237         local mach="${o_mach:-pc}"
 238         local qemu_exe
 239
 240         [ -n "$rootfs" ] || {
 241                 rootfs="$o_bindir/openwrt-$o_target-${o_subtarget%-*}-combined-ext4.img"
 242                 if [ ! -f "$rootfs" -a -s "$rootfs.gz" ]; then
 243                         gunzip "$rootfs.gz"
 244                 fi
 245         }
 246         #
 247         # generic: 32-bit, pentium4 (CONFIG_MPENTIUM4), kvm guest, virtio
 248         # legacy: 32-bit, i486 (CONFIG_M486)
 249         # 64: 64-bit, kvm guest, virtio
 250         #
 251         case "${o_subtarget%-*}" in
 252                 legacy)                 qemu_exe="qemu-system-i386"     ;;
 253                 generic|64)             qemu_exe="qemu-system-x86_64"   ;;
 254                 *)
 255                         __errmsg "target $o_target: unknown subtarget $o_subtarget"
 256                         return 1
 257                         ;;
 258         esac
 259
 260         [ -n $o_nonetwork ] || {
 261                 o_qemu_extra+=( \
 262                         "-netdev" "bridge,id=lan,br=$BR_LAN,helper=$HELPER" \
 263                             "-device" "virtio-net-pci,id=devlan,netdev=lan,mac=$MAC_LAN" \
 264                         "-netdev" "bridge,id=wan,br=$BR_WAN,helper=$HELPER" "-device" \
 265                             "virtio-net-pci,id=devwan,netdev=wan,mac=$MAC_WAN" \
 266                 )
 267         }
 268
 269         case "${o_subtarget%-*}" in
 270                 legacy)
 271                         # use IDE (PATA) disk instead of AHCI (SATA).  Refer to link
 272                         # [1] for related discussions
 273                         #
 274                         # To use AHCI interface
 275                         #
 276                         #       -device ich9-ahci,id=ahci \
 277                         #       -device ide-drive,drive=drv0,bus=ahci.0 \
 278                         #       -drive "file=$rootfs,format=raw,id=drv0,if=none" \
 279                         #
 280                         # [1] https://dev.openwrt.org/ticket/17947
 281                         "$qemu_exe" -machine "$mach" -nographic \
 282                                 -device ide-drive,drive=drv0 \
 283                                 -drive "file=$rootfs,format=raw,id=drv0,if=none" \
 284                                 "${o_qemu_extra[@]}"
 285                         ;;
 286                 generic|64)
 287                         "$qemu_exe" -machine "$mach" -nographic \
 288                                 -drive "file=$rootfs,format=raw,if=virtio" \
 289                                 "${o_qemu_extra[@]}"
 290                         ;;
 291         esac
 292 }
 293
 294 start_qemu() {
 295         case "$o_target" in
 296                 armvirt)        start_qemu_armvirt      ;;
 297                 malta)          start_qemu_malta        ;;
 298                 x86)            start_qemu_x86          ;;
 299                 *)
 300                         __errmsg "target $o_target is not supported yet"
 301                         return 1
 302                         ;;
 303         esac
 304 }
 305
 306 parse_args "$@" \
 307         && check_setup \
 308         && start_qemu