text: # This file is Copyright 2020 Volatility Foundation and licensed under the Volatility Software License 1.0
  # which is available at https://www.volatilityfoundation.org/license/vsl-v1.0
  #
  import logging
  from typing import List
  
  from volatility.framework import interfaces, renderers, layers
  from volatility.framework.configuration import requirements
  from volatility.framework.layers import scanners
  from volatility.framework.renderers import format_hints
  
  vollog = logging.getLogger(__name__)
  
  
  class Banners(interfaces.plugins.PluginInterface):
      """Attempts to identify potential linux banners in an image"""
  
      @classmethod
      def get_requirements(cls) -> List[interfaces.configuration.RequirementInterface]:
          return [requirements.TranslationLayerRequirement(name = 'primary', description = 'Memory layer to scan')]
  
      def _generator(self):
          layer = self.context.layers[self.config['primary']]
          if isinstance(layer, layers.intel.Intel):
              layer = self.context.layers[layer.config['memory_layer']]
          for offset, banner in self.locate_banners(self.context, layer.name):
              yield 0, (offset, banner)
  
      @classmethod
      def locate_banners(cls, context: interfaces.context.ContextInterface, layer_name: str):
          """Identifies banners from a memory image"""
          layer = context.layers[layer_name]
          for offset in layer.scan(context = context,
                                   scanner = scanners.RegExScanner(
                                       rb"(Linux version|Darwin Kernel Version) [0-9]+\.[0-9]+\.[0-9]+")):
              data = layer.read(offset, 0xfff)
              data_index = data.find(b'\x00')
              if data_index > 0:
                  data = data[:data_index].strip()
                  failed = [
                      char for char in data
                      if char not in b' #()+,;/-.0123456789:@ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz~'
                  ]
                  if not failed:
                      yield format_hints.Hex(offset), str(data, encoding = 'latin-1', errors = '?')
  
      def run(self):
          return renderers.TreeGrid([("Offset", format_hints.Hex), ("Banner", str)], self._generator())
  