metasploit-framework/lib/rex/peparsey/section.rb

130 lines
2.7 KiB
Ruby

#!/usr/bin/env ruby
# -*- coding: binary -*-
require 'rex/peparsey/exceptions'
require 'rex/peparsey/pebase'
require 'rex/struct2'
module Rex
module PeParsey
class Section
attr_accessor :_section_header, :_isource
attr_accessor :base_rva
#
# Initialize a section.
#
# isource - The ImageSource class backing the image
# base_vma - The address of this section base
# section_header - The section header (struct2) although this is not
# required, which is why there is a base_vma. This can be nil.
#
def initialize(isource, base_rva, section_header = nil)
self._isource = isource
self.base_rva = base_rva
self._section_header = section_header
end
def file_offset
_isource.file_offset
end
def size
_isource.size
end
def name
# a section header is not required
return nil if !_section_header
# FIXME make this better...
_section_header.v['Name'].gsub(/\x00+$/, '')
end
def flags
# a section header is not required
return nil if !_section_header
_section_header.v['Characteristics']
end
def vma
# a section header is not required
return nil if !_section_header
_section_header.v['VirtualAddress']
end
def raw_size
# a section header is not required
return nil if !_section_header
_section_header.v['SizeOfRawData']
end
def _check_offset(offset, len = 1)
if offset < 0 || offset+len > size
raise BoundsError, "Offset #{offset} outside of section", caller
end
end
def read(offset, len)
_check_offset(offset, len)
return _isource.read(offset, len)
end
def read_rva(rva, len)
return read(rva_to_offset(rva), len)
end
def read_asciiz(offset)
_check_offset(offset)
return _isource.read_asciiz(offset)
end
def read_asciiz_rva(rva)
return read_asciiz(rva_to_offset(rva))
end
def index(*args)
_isource.index(*args)
end
def offset_to_rva(offset)
if !contains_offset?(offset)
raise BoundsError, "Offset #{offset} outside of section", caller
end
return offset + base_rva
end
def file_offset_to_rva(foffset)
return offset_to_rva(foffset - file_offset)
end
def rva_to_offset(rva)
offset = rva - base_rva
if !contains_offset?(offset)
raise BoundsError, "RVA #{rva} outside of section", caller
end
return offset
end
def rva_to_file_offset(rva)
return rva_to_offset(rva) + file_offset
end
def contains_offset?(offset)
offset >= 0 && offset < size
end
def contains_file_offset?(foffset)
contains_offset?(foffset - file_offset)
end
def contains_rva?(rva)
contains_offset?(rva - base_rva)
end
end
end end