#!/bin/sh

# Copyright (C) 2008,2009 Citrix Systems, Inc. All rights reserved.
# Copyright (C) 2009 Nicira Networks, Inc.

# CA-23900: Warning: when VIFs are added to windows guests with PV drivers the backend vif device is registered,
# unregistered and then registered again. This causes the udev event to fire twice and this script runs twice.
# Since the first invocation of the script races with the device unregistration, spurious errors are possible
# which will be logged but are safe to ignore since the second script invocation should complete the operation.
# Note that each script invocation is run synchronously from udev and so the scripts don't race with each other.

# Keep other-config/ keys in sync with device.ml:vif_udev_keys

cfg_mod="/usr/bin/ovs-cfg-mod"
vsctl="/usr/bin/ovs-vsctl"
dump_vif_details="/usr/share/vswitch/scripts/dump-vif-details"
service="/sbin/service"
IP="/sbin/ip"
vif_on_internal_bridge="/usr/share/vswitch/scripts/vif-on-internal-bridge"

handle_promiscuous()
{
    local arg=$(xenstore-read "${PRIVATE}/other-config/promiscuous" 2>/dev/null)
    if [ $? -eq 0 -a -n "${arg}" ] ; then
        case "${arg}" in 
            true|on) logger -t script-vif "${dev}: Promiscuous ports are not supported via vSwitch." ;;
            *) ;;
        esac
    fi
}

handle_ethtool()
{
    local opt=$1
    local arg=$(xenstore-read "${PRIVATE}/other-config/ethtool-${opt}" 2>/dev/null)
    if [ $? -eq 0 -a -n "${arg}" ] ; then
        case "${arg}" in
            true|on)   /sbin/ethtool -K "${dev}" "${opt}" on ;;
            false|off) /sbin/ethtool -K "${dev}" "${opt}" off ;;
            *) logger -t scripts-vif "Unknown ethtool argument ${opt}=${arg} on ${dev}/${VIFUUID}" ;;
        esac
    fi
}

handle_mtu()
{
    local mtu=$(xenstore-read "${PRIVATE}/MTU" 2>/dev/null)
    if [ $? -eq 0 -a -n "${mtu}" ]; then
	echo "${mtu}" > /sys/class/net/${dev}/mtu
    fi
}

handle_vif_details()
{
    local vif_details=
    local net_uuid=$(xenstore-read "${PRIVATE}/network-uuid" 2>/dev/null)
    if [ -n "${net_uuid}" ] ; then
	vif_details="$vif_details --add=port.${dev}.net-uuid=${net_uuid}"
    fi

    local address=$(xenstore-read "/local/domain/$DOMID/device/vif/$DEVID/mac" 2>/dev/null)
    if [ -n "${address}" ] ; then
	vif_details="$vif_details --add=port.${dev}.vif-mac=${address}"
    fi

    local vif_uuid=$(xenstore-read "${PRIVATE}/vif-uuid" 2>/dev/null)
    if [ -n "${vif_uuid}" ] ; then
	vif_details="$vif_details --add=port.${dev}.vif-uuid=${vif_uuid}"
    fi

    local vm=$(xenstore-read "/local/domain/$DOMID/vm" 2>/dev/null)
    if [ $? -eq 0 -a -n "${vm}" ] ; then
	local vm_uuid=$(xenstore-read "$vm/uuid" 2>/dev/null)
    fi
    if [ -n "${vm_uuid}" ] ; then
	vif_details="$vif_details --add=port.${dev}.vm-uuid=${vm_uuid}"
    fi

    # vNetManager needs to know the network UUID(s) associated with
    # each datapath.  Normally interface-reconfigure adds them, but
    # interface-reconfigure never gets called for internal networks
    # (xapi does the addbr ioctl internally), so we have to do it
    # here instead for internal networks.  This is only acceptable
    # because xapi is lazy about creating internal networks: it
    # only creates one just before it adds the first vif to it.
    # There may still be a brief delay between the initial
    # ovs-vswitchd connection to vNetManager and setting this
    # configuration variable, but vNetManager can tolerate that.
    local internal=$(${vif_on_internal_bridge} ${DOMID} ${DEVID})
    if [ "$internal" = "true" ]; then
        local bridge=$(xenstore-read "${PRIVATE}/bridge" 2>/dev/null)
        local net_uuid=$(xenstore-read "${PRIVATE}/network-uuid" 2>/dev/null)
        local key="bridge.${bridge}.xs-network-uuids"

        vif_details="$vif_details --del-match=${key}=*"
        vif_details="$vif_details --add=${key}=${net_uuid}"
    fi

    echo ${vif_details}
}

add_to_bridge()
{
    local address=$(xenstore-read "${PRIVATE}/bridge-MAC")
    if [ $? -ne 0 -o -z "${address}" ]; then
	logger -t scripts-vif "Failed to read ${PRIVATE}/bridge-MAC from xenstore"
	exit 1
    fi
    local bridge=$(xenstore-read "${PRIVATE}/bridge")
    if [ $? -ne 0 -o -z "${bridge}" ]; then
	logger -t scripts-vif "Failed to read ${PRIVATE}/bridge from xenstore"
	exit 1
    fi
    logger -t scripts-vif "Adding ${dev} to ${bridge} with address ${address}"

    local VLAN_ID=$($vsctl br-to-vlan $bridge)
    local vid=
    if [ "$VLAN_ID" -ne 0 ] ; then
	bridge=$($vsctl br-to-parent $bridge)
	vid="--add=vlan.${dev}.tag=${VLAN_ID}"
    fi

    if [ "$type" = "vif" ] ; then
	local vif_details=$(handle_vif_details)
    fi

    ${IP} link set "${dev}" down                        || logger -t scripts-vif "Failed to ip link set ${dev} down"
    ${IP} link set "${dev}" arp off                     || logger -t scripts-vif "Failed to ip link set ${dev} arp off"
    ${IP} link set "${dev}" multicast off               || logger -t scripts-vif "Failed to ip link set ${dev} multicast off"
    ${IP} link set "${dev}" address "${address}"        || logger -t scripts-vif "Failed to ip link set ${dev} address ${address}"
    ${IP} addr flush "${dev}"                           || logger -t scripts-vif "Failed to ip addr flush ${dev}"

    $cfg_mod -F /etc/ovs-vswitchd.conf \
        --del-match="bridge.*.port=${dev}" \
        --del-match="vlan.${dev}.[!0-9]*" \
        --del-match="port.${dev}.[!0-9]*" \
        --add="bridge.$bridge.port=${dev}" \
        $vid $vif_details -c 
    $service vswitch reload

    ${IP} link set "${dev}" up                          || logger -t scripts-vif "Failed to ip link set ${dev} up"
}

type=$2

case ${type} in
    vif)
	DOMID=`echo ${XENBUS_PATH} | cut -f 3 -d '/'`
	DEVID=`echo ${XENBUS_PATH} | cut -f 4 -d '/'`
	dev=vif${DOMID}.${DEVID}
	;;
    tap)
	dev=$INTERFACE
	DOMID=`echo ${dev#tap} | cut -f 1 -d '.'`
	DEVID=`echo ${dev#tap} | cut -f 2 -d '.'`
	;;
    *)  
	logger -t scripts-vif "unknown interface type ${type}"
	exit 1
	;;
esac

XAPI=/xapi/${DOMID}/hotplug/vif/${DEVID}
HOTPLUG=/xapi/${DOMID}/hotplug/vif/${DEVID}
PRIVATE=/xapi/${DOMID}/private/vif/${DEVID}

echo Called as "$@" "$DOMID" "$DEVID" | logger -t scripts-vif
case "$1" in
online)
	if [ "${type}" = "vif" ] ; then
	    handle_ethtool rx
	    handle_ethtool tx
	    handle_ethtool sg
	    handle_ethtool tso
	    handle_ethtool ufo
	    handle_ethtool gso

	    handle_mtu
	    add_to_bridge
	    handle_promiscuous

	    xenstore-write "${HOTPLUG}/vif" "${dev}"
	    xenstore-write "${HOTPLUG}/hotplug" "online"

	    # xs-xen.pq.hq:91e986b8e49f netback-wait-for-hotplug
	    xenstore-write "/local/domain/0/backend/vif/${DOMID}/${DEVID}/hotplug-status" "connected"
	fi
	;;

add)
	if [ "${type}" = "tap" ] ; then
	    add_to_bridge
	fi
	;;

remove)
	if [ "${type}" = "vif" ] ;then
	    xenstore-rm "${HOTPLUG}/hotplug"
	fi
	logger -t scripts-vif "${dev} has been removed"
	$cfg_mod -vANY:console:emer -F /etc/ovs-vswitchd.conf \
	    --del-match="bridge.*.port=${dev}" \
	    --del-match="vlan.${dev}.[!0-9]*" \
	    --del-match="port.${dev}.[!0-9]*" -c
	$service vswitch reload
	;;
esac