#!/bin/sh -e

# Copyright (C) 2013 Andrew Shadura

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU Library General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.

usage () {
cat <<EOF

Usage: add             [interface-name] [vlan_id]
       rem             [vlan-name]
       set_flag        [interface-name] [flag-num]       [0 | 1]
       set_egress_map  [vlan-name]      [skb_priority]   [vlan_qos]
       set_ingress_map [vlan-name]      [skb_priority]   [vlan_qos]
       set_name_type   [name-type]

* The [interface-name] is the name of the ethernet card that hosts
  the VLAN you are talking about.
* The vlan_id is the identifier (0-4095) of the VLAN you are operating on.
* skb_priority is the priority in the socket buffer (sk_buff).
* vlan_qos is the 3 bit priority in the VLAN header
* name-type:  VLAN_PLUS_VID (vlan0005), VLAN_PLUS_VID_NO_PAD (vlan5),
              DEV_PLUS_VID (eth0.0005), DEV_PLUS_VID_NO_PAD (eth0.5)
* FLAGS:  1 REORDER_HDR  When this is set, the VLAN device will move the
            ethernet header around to make it look exactly like a real
            ethernet device.  This may help programs such as DHCPd which
            read the raw ethernet packet and make assumptions about the
            location of bytes.  If you don't need it, don't turn it on, because
            there will be at least a small performance degradation.  Default
            is OFF.
EOF
}

ARGC=$(expr $# + 1)

STATEDIR=/run/network/vlan

echo "" >&2
echo "Warning: vconfig is deprecated and might be removed in the future, please migrate to ip(route2) as soon as possible!" >&2
echo "" >&2

if [ $ARGC -lt 3 -o $ARGC -gt 5 ]
then
    echo "Expecting argc to be 3-5, inclusive.  Was: $ARGC" >&2
    usage
    exit 1
fi

ip () {
    /sbin/ip "$@"
}

condret () {
    [ "$1" = "$2" ] && echo -n "$3"
}

map () {
    v="$1"
    shift
    for pq in "$@"
    do
        condret "$v" $pq && return 0
    done
    false
}

add () {
    NAME_TYPE=DEV_PLUS_VID_NO_PAD
    [ -r "$STATEDIR/name-type" ] && NAME_TYPE=$(cat "$STATEDIR/name-type")

    VLAN_ID="$2"
    IFACE="$1"

    case "$NAME_TYPE" in
        VLAN_PLUS_VID)
            NAME="$(printf vlan%.4d "$VLAN_ID")"
            ;;
        VLAN_PLUS_VID_NO_PAD)
            NAME="vlan$VLAN_ID"
            ;;
        DEV_PLUS_VID)
            NAME="$(printf %s.%.4d "$IFACE" "$VLAN_ID")"
            ;;
        DEV_PLUS_VID_NO_PAD)
            NAME="$IFACE.$VLAN_ID"
            ;;
    esac
    ip link add link "$IFACE" name "$NAME" type vlan id "$VLAN_ID" || exit 3
}

rem () {
    ip link del "$1" || exit 4
}

set_name_type () {
    mkdir -p "$STATEDIR" || exit 8
    echo "$1" > "$STATEDIR/name-type" || exit 8
}

set_flag () {
    echo "$@"
    if FLAG=$(map "$3" "0 off" "1 on")
    then
        ip link set dev "$1" type vlan reorder_hdr "$FLAG" || exit 7
    else
        echo "Invalid flag parameter specified" >&2
        exit 7
    fi
}

set_ingress_map () {
    ip link set dev "$1" type vlan ingress-qos-map "$2:$3" || exit 6
}

set_egress_map () {
    ip link set dev "$1" type vlan egress-qos-map "$2:$3" || exit 5
}

case "$1" in
    add)
        add "$2" "$3"
        ;;
    rem)
        rem "$2"
        ;;
    set_flag)
        set_flag "$2" "$3" "$4"
        ;;
    set_ingress_map)
        set_ingress_map "$2" "$3" "$4"
        ;;
    set_egress_map)
        set_egress_map "$2" "$3" "$4"
        ;;
    set_name_type)
        set_name_type "$2"
        ;;
    *)
        echo "Unknown command: $1" >&2
        exit 5
        ;;
esac