# This file was contributed to the Volatility Framework Version 3.
# Copyright (C) 2018 Volatility Foundation.
#
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from typing import List

import volatility.framework.interfaces.plugins as interfaces_plugins
import volatility.framework.interfaces.renderers as interfaces_renderers
import volatility.plugins.linux.pslist as pslist
from volatility.framework import constants, interfaces
from volatility.framework import renderers
from volatility.framework.configuration import requirements
from volatility.framework.objects import utility
from volatility.framework.renderers import format_hints


class Malfind(interfaces_plugins.PluginInterface):
    """Lists process memory ranges that potentially contain injected code"""

    @classmethod
    def get_requirements(cls) -> List[interfaces.configuration.RequirementInterface]:
        return [
            requirements.TranslationLayerRequirement(
                name = 'primary', description = 'Memory layer for the kernel', architectures = ["Intel32", "Intel64"]),
            requirements.SymbolTableRequirement(name = "vmlinux", description = "Linux kernel symbols")
        ]

    def _list_injections(self, task):
        """Generate memory regions for a process that may contain
        injected code.
        """

        proc_layer_name = task.add_process_layer()
        if not proc_layer_name:
            return

        proc_layer = self.context.layers[proc_layer_name]

        for vma in task.mm.get_mmap_iter():
            if vma.is_suspicious() and vma.get_name(self.context, task) != "[vdso]":
                data = proc_layer.read(vma.vm_start, 64, pad = True)
                yield vma, data

    def _generator(self, tasks):
        # determine if we're on a 32 or 64 bit kernel
        if self.context.symbol_space.get_type(self.config["vmlinux"] + constants.BANG + "pointer").size == 4:
            is_32bit_arch = True
        else:
            is_32bit_arch = False

        for task in tasks:
            process_name = utility.array_to_string(task.comm)

            for vma, data in self._list_injections(task):
                if is_32bit_arch:
                    architecture = "intel"
                else:
                    architecture = "intel64"

                disasm = interfaces_renderers.Disassembly(data, vma.vm_start, architecture)

                yield (0, (task.pid, process_name, format_hints.Hex(vma.vm_start), format_hints.Hex(vma.vm_end),
                           vma.get_protection(), format_hints.HexBytes(data), disasm))

    def run(self):
        filter_func = pslist.PsList.create_pid_filter([self.config.get('pid', None)])

        return renderers.TreeGrid([("PID", int), ("Process", str), ("Start", format_hints.Hex),
                                   ("End", format_hints.Hex), ("Protection", str), ("Hexdump", format_hints.HexBytes),
                                   ("Disasm", interfaces_renderers.Disassembly)],
                                  self._generator(
                                      pslist.PsList.list_tasks(
                                          self.context,
                                          self.config['primary'],
                                          self.config['vmlinux'],
                                          filter_func = filter_func)))