Class: OneGadget::Gadget::Gadget

Inherits:
Object
  • Object
show all
Defined in:
lib/one_gadget/gadget.rb

Overview

Information of a gadget.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(offset, **options) ⇒ Gadget

Initialize method of OneGadget::Gadget::Gadget instance.

Examples:

OneGadget::Gadget::Gadget.new(0x12345, constraints: ['rax == 0'])

Parameters:

  • offset (Integer) —

    The relative address offset of this gadget.

  • options (Hash) —

    a customizable set of options

Options Hash (**options):

  • :constraints (Array<String>) —

    The constraints need for this gadget. Defaults to [].



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# File 'lib/one_gadget/gadget.rb', line 27

def initialize(offset, **options)
  @base = 0
  @offset = offset
  @constraints = options[:constraints] || []
  @effect = options[:effect]
end

Instance Attribute Details

#base ⇒ Integer

Returns Base address of libc. Default: 0.

Returns:

  • (Integer) —

    Base address of libc. Default: 0.



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# File 'lib/one_gadget/gadget.rb', line 13

def base
  @base
end

#constraints ⇒ Array<String> (readonly)

Returns The constraints need for this gadget.

Returns:

  • (Array<String>) —

    The constraints need for this gadget.



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# File 'lib/one_gadget/gadget.rb', line 17

def constraints
  @constraints
end

#effect ⇒ String (readonly)

Returns The final result of this gadget.

Returns:

  • (String) —

    The final result of this gadget.



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# File 'lib/one_gadget/gadget.rb', line 19

def effect
  @effect
end

#offset ⇒ Integer (readonly)

Returns The gadget’s address offset.

Returns:

  • (Integer) —

    The gadget’s address offset.



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# File 'lib/one_gadget/gadget.rb', line 15

def offset
  @offset
end

Instance Method Details

#inspect ⇒ Object

Show gadget in a pretty way.



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# File 'lib/one_gadget/gadget.rb', line 35

def inspect
  str = OneGadget::Helper.hex(value)
  str += effect ? " #{effect}\n" : "\n"
  unless constraints.empty?
    str += "#{OneGadget::Helper.colorize('constraints')}:\n  "
    str += merge_constraints.join("\n  ")
  end
  str.gsub!(/0x[\da-f]+/) { |s| OneGadget::Helper.colorize(s, sev: :integer) }
  OneGadget::ABI.all.each do |reg|
    str.gsub!(/([^\w])(#{reg})([^\w])/, "\\1#{OneGadget::Helper.colorize('\2', sev: :reg)}\\3")
  end
  "#{str}\n"
end

#score ⇒ Float

Returns The success probability of the constraints.

Returns:

  • (Float) —

    The success probability of the constraints.



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# File 'lib/one_gadget/gadget.rb', line 57

def score
  @score ||= constraints.reduce(1.0) { |s, c| s * calculate_score(c) }
end

#value ⇒ Integer

Returns base plus offset.

Returns:

  • (Integer) —

    Returns base plus offset.



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# File 'lib/one_gadget/gadget.rb', line 51

def value
  base + offset
end