# Volatility
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU 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 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 

"""
@author:       Andrew Case
@license:      GNU General Public License 2.0 or later
@contact:      atcuno@gmail.com
@organization: Digital Forensics Solutions
"""

import volatility.obj as obj
import volatility.plugins.linux.common as linux_common

class linux_route_cache(linux_common.AbstractLinuxCommand):
    """ Recovers the routing cache from memory """

    def calculate(self):
        linux_common.set_plugin_members(self)

        mask = obj.Object("unsigned int", offset = self.addr_space.profile.get_symbol("rt_hash_mask"), vm = self.addr_space)
        rt_pointer = obj.Object("Pointer", offset = self.addr_space.profile.get_symbol("rt_hash_table"), vm = self.addr_space)
        rt_hash_table = obj.Object(theType = "Array", offset = rt_pointer, vm = self.addr_space, targetType = "rt_hash_bucket", count = mask)

        # rt_do_flush / rt_cache_seq_show
        for i in range(mask):

            rth = rt_hash_table[i].chain

            if not rth:
                continue

            while rth:
 
                # FIXME: Consider using kernel version metadata rather than checking hasattr
                if hasattr(rth, 'u'):
                    dst = rth.u.dst
                    nxt = rth.u.dst.rt_next
                else:
                    dst = rth.dst
                    nxt = rth.dst.rt_next

                if dst.dev:
                    name = dst.dev.name
                else:
                    name = "*"

                dest = rth.rt_dst
                gw = rth.rt_gateway

                yield (name, dest, gw)

                rth = nxt

    def render_text(self, outfd, data):

        self.table_header(outfd, [("Interface", "16"),
                                  ("Destination", "20"),
                                  ("Gateway", "")])

        for (name, dest, gw) in data:
            self.table_row(outfd, name, dest.cast("IpAddress"), gw.cast("IpAddress"))