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Editing: ifup-tunnel

#!/bin/bash
# Copyright (C) 1996-2009 Red Hat, Inc. all rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2,
# as published by the Free Software Foundation.
#
# 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 General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

# Thanks to:
#  - Razvan Corneliu C.R. Vilt <razvan.vilt@linux360.ro>
#  - Aaron Hope <aaron.hope@unh.edu>
#  - Sean Millichamp <sean@enertronllc.com>
# for providing the scripts this one is based on

. /etc/init.d/functions

cd /etc/sysconfig/network-scripts
. ./network-functions

CONFIG=$1
need_config "$CONFIG"
source_config

if [ "$PEER_OUTER_IPADDR" = "$PEER_INNER_IPADDR" ]; then
    # Specifying PEER_INNER_IPADDR would automatically add a route to the peer
    # through the tunnel, redirecting tunnel packets back to the tunnel and
    # creating a dead loop.
    unset PEER_INNER_IPADDR
fi

case "$TYPE" in
GRE)
    MODE=gre
    proto=-4
    /sbin/modprobe ip_gre
    ;;
GRE6)
    MODE=ip6gre
    proto=-6
    /sbin/modprobe ip6_gre
    ;;
IPIP)
    MODE=ipip
    proto=-4
    /sbin/modprobe ipip
    ;;
IPIP6|EXTERNAL)
    MODE=ipip6
    proto=-6
    /sbin/modprobe ip6_tunnel
    ;;
*)
    net_log $"Invalid tunnel type $TYPE"
    exit 1
    ;;
esac

# Generic tunnel devices are not supported here
if [ "$DEVICE" = gre0 -o "$DEVICE" = tunl0 -o "$DEVICE" = ip6tnl0 ]; then
    net_log $"Device '$DEVICE' isn't supported as a valid GRE device name."
    exit 1
fi

# Create the tunnel
# The outer addresses are those of the underlying (public) network.
if [ "$TYPE" = 'EXTERNAL' ]; then
  /sbin/ip link add "$DEVICE" type ip6tnl external
else
  /sbin/ip $proto tunnel add "$DEVICE" mode "$MODE" \
      ${MY_OUTER_IPADDR:+local "$MY_OUTER_IPADDR"} \
      ${PEER_OUTER_IPADDR:+remote "$PEER_OUTER_IPADDR"} \
      ${KEY:+key "$KEY"} ${TTL:+ttl "$TTL"}
fi

if [ -n "$MTU" ]; then
    /sbin/ip link set "$DEVICE" mtu "$MTU"
fi

# The inner address are used mainly for communication between a gateway
# and a private network.  When the peer is configured with an inner address
# contained in the peer's private network or identical to it's public address,
# it need not be specified.
/sbin/ip addr add "$MY_INNER_IPADDR" dev "$DEVICE" \
    ${PEER_INNER_IPADDR:+peer "$PEER_INNER_IPADDR"}

set_link_up "${DEVICE}"

# IPv6 initialisation?
/etc/sysconfig/network-scripts/ifup-ipv6 ${CONFIG}

exec /etc/sysconfig/network-scripts/ifup-post "$CONFIG" "$2"

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