# Volatility
# Copyright (C) 2007-2013 Volatility Foundation
#
# This file is part of Volatility.
#
# Volatility 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.  You may not use, modify or
# distribute this program under any other version of the GNU General
# Public License.
#
# Volatility 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 Volatility.  If not, see <http://www.gnu.org/licenses/>.
#

"""
@author:       Andrew Case
@license:      GNU General Public License 2.0
@contact:      atcuno@gmail.com
@organization: 
"""

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

class linux_ldrmodules(linux_pslist.linux_pslist):
    """Compares the output of proc maps with the list of libraries from libdl"""

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

        procs = linux_pslist.linux_pslist(self._config).calculate()
        proc_maps = {}
        dl_maps   = {}
        seen_starts = []

        for task in procs:
            proc_maps[task.obj_offset] = {}
            proc_as = task.get_process_address_space()        

            for vma in task.get_proc_maps():
                sig = proc_as.read(vma.vm_start, 4)
                
                if sig == "\x7fELF":
                    flags = str(vma.vm_flags)
           
                    if flags in ["rw-", "r--"]:
                        continue 

                    if vma.vm_file: 
                        fname = linux_common.get_path(task, vma.vm_file)
                    elif vma.vm_start <= task.mm.start_brk and vma.vm_end >= task.mm.brk:
                        fname = "[heap]"
                    elif vma.vm_start <= task.mm.start_stack and vma.vm_end >= task.mm.start_stack:
                        fname = "[stack]"
                    elif vma.vm_start == vma.vm_mm.context.vdso:
                        continue
                    else:
                        fname = ""
         
                    proc_maps[task.obj_offset][vma.vm_start.v()] = (task, proc_as, fname)

            dl_maps[task.obj_offset] = {}
            for so in task.get_libdl_maps():
                if so.l_addr == 0x0 or len(str(so.l_name)) == 0:
                    continue
                dl_maps[task.obj_offset][so.l_addr.v()] = (task, proc_as, str(so.l_name))
    
        for task_offset in proc_maps:
            for vm_start in proc_maps[task_offset]:
                (task, proc_as, vm_name) = proc_maps[task_offset][vm_start]
                seen_starts.append(vm_start)
                yield (task_offset, task, proc_as, vm_start, vm_name, proc_maps, dl_maps)

        for task_offset in dl_maps:
            for vm_start in dl_maps[task_offset]:
                if vm_start in seen_starts:
                    continue

                (task, proc_as, vm_name) = dl_maps[task_offset][vm_start] 
                yield (task_offset, task, proc_as, vm_start, vm_name, proc_maps, dl_maps)

    def render_text(self, outfd, data):
        self.table_header(outfd, [("Pid", "8"),
                                  ("Name", "16"),
                                  ("Start", "#018x"),
                                  ("File Path", "50"),                    
                                  ("Kernel", "6"),
                                  ("Libc", "6"), 
                                ]) 

        for task_offset, task, proc_as, vm_start, vma_name, proc_maps, dl_maps in data:
            if vm_start in proc_maps[task_offset]:
                pmaps = "True"
            else:
                pmaps = "False"

            if vm_start in dl_maps[task_offset]:
                dmaps = "True"
            else:
                dmaps = "False"

            self.table_row(outfd, 
                task.pid, 
                str(task.comm),
                vm_start,
                vma_name,
                pmaps,
                dmaps)