vm

#!/bin/bash
set -e

debug=0
reset=0
bridge=virbr0
storage=
basepath="$HOME/.cache/vm/"
image="$basepath/vmlinuz.efi"
kernelargs=""

usage() {
   cat <<EOF
Usage: vm -n $name [ -r ] [ -d ]
   -n $name: name of the vm
   -d: run in debug mode
   -r: reset vm (recreate disks)
   -b: Bridge name defaults to virbr0
   -s: Storage bridge name defaults to storage
   -c: Kernel args
   -i: Kernel image
   -h: help

EOF
   exit 0
}


while getopts "c:n:i:rdb:s:" opt; do
   case $opt in
   i )  image=$OPTARG ;;
   r )  reset=1 ;;
   d )  debug=1 ;;
   b )  bridge=$OPTARG ;;
   s )  storage=$OPTARG ;;
   n )  name=$OPTARG ;;
   c )  kernelargs=$OPTARG ;;
   i )  image=$OPTARG ;;
   h )  usage ; exit 0 ;;
   \?)  usage ; exit 1 ;;
   esac
done
shift $(($OPTIND - 1))


cmdline="console=ttyS1,115200n8 $kernelargs"
vmdir="$basepath/$name"
md5=$(echo -n $name | md5sum | awk '{print $1}')
uuid="${md5:0:8}-${md5:8:4}-${md5:12:4}-${md5:16:4}-${md5:20}"
basemac="54:${md5:2:2}:${md5:4:2}:${md5:6:2}:${md5:8:2}:${md5:10:1}"
storageline=""

createdisks() {
    mkdir -p $vmdir
    qemu-img create -f qcow2 $vmdir/vda.qcow2 50G
    qemu-img create -f qcow2 $vmdir/vdb.qcow2 50G
    qemu-img create -f qcow2 $vmdir/vdc.qcow2 50G
    qemu-img create -f qcow2 $vmdir/vdd.qcow2 50G
    qemu-img create -f qcow2 $vmdir/vde.qcow2 50G

}

if [[ ! -d "$vmdir" || "$reset" -eq 1 ]]; then
    mkdir -p "$vmdir"
    createdisks
fi

if ps -eaf | grep -v grep | grep "$uuid" > /dev/null; then
    echo "VM $name is already running"
    exit 1
fi

overlay="$vmdir/overlay"

mkdir -p "$vmdir/overlay/etc/zero-os/conf/"
touch "$vmdir/overlay/.zero-os-debug"
cat << EOF > "$vmdir/overlay/etc/zero-os/conf/ash.toml"
[startup.ashlogin]
name = "bash"
after = ["init"]

[startup.ashlogin.args]
script = """
# Enable ip forwarding
while true; do
getty -l /bin/ash -n 19200 ttyS1
done
"""
EOF

netfile="$vmdir/overlay/etc/zero-os/network.toml"
if [[ "$bridge" == "docker0" && ! -e "$netfile" ]]; then
cat << EOF > "$netfile"
[network]
auto = false

[interface.eth0]
protocol = "static"

[static.eth0]
ip = "172.17.2.$(( 16#${md5:10:2} ))/16"
gateway = "172.17.0.1"

[interface.lo]
protocol = "static"

[static.lo]
ip = "127.0.0.1/8"
EOF
cat << EOF > "$vmdir/overlay/etc/resolv.conf"
nameserver 8.8.8.8
EOF
fi

if [ ! -e /sys/class/net/$bridge ]; then
    echo "Management bridge $bridge does not exists!"
    echo "  Maybe default network isn't started? Try 'virsh net-start default'"
    exit 1
fi

if [ ! -e /etc/qemu/bridge.conf ]; then
    sudo mkdir -p /etc/qemu
    sudo tee /etc/qemu/bridge.conf << EOF
allow $bridge
EOF
fi
if ! grep $bridge /etc/qemu/bridge.conf > /dev/null; then
    sudo tee -a /etc/qemu/bridge.conf << EOF
allow $bridge
EOF
fi

if [ -n "$storage" ]; then
    if [ ! -e /sys/class/net/$storage ]; then
        sudo ip l a $storage type bridge
    fi
    if ! grep $storage /etc/qemu/bridge.conf > /dev/null; then
        sudo tee -a /etc/qemu/bridge.conf << EOF
    allow $storage
EOF
    fi
    storageline="-netdev bridge,id=storage,br=$storage -device virtio-net-pci,netdev=storage,mac=${basemac}2"
fi



qemu-system-x86_64 -kernel $image \
    -m 4096 -enable-kvm -cpu host \
    -uuid $uuid \
    -netdev bridge,id=management,br=$bridge -device virtio-net-pci,netdev=management,mac="${basemac}1" \
    $storageline \
    -drive file=fat:rw:$overlay,format=raw \
    -serial null -serial mon:stdio \
    -append "${cmdline}" \
    -drive file=$vmdir/vda.qcow2,if=virtio -drive file=$vmdir/vdb.qcow2,if=virtio \
    -drive file=$vmdir/vdc.qcow2,if=virtio -drive file=$vmdir/vdd.qcow2,if=virtio \
    -drive file=$vmdir/vde.qcow2,if=virtio \
    -nographic -nodefaults