Module: PWN::Plugins::Assembly

Defined in:
lib/pwn/plugins/assembly.rb

Overview

This plugin converts images to readable text

Class Method Summary collapse

Class Method Details

.asm_to_opcodes(opts = {}) ⇒ Object

Supported Method Parameters

PWN::Plugins::Assembly.asm_to_opcodes(

asm: 'required - assembly instruction(s) (e.g. 'nop\nnop\nnop\njmp rsp\n)',
arch: 'optional - architecture returned from objdump --info (defaults to PWN::Plugins::DetectOS.arch)',
endian: 'optional - endianess :big|:little (defaults to current system endianess)'

)



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# File 'lib/pwn/plugins/assembly.rb', line 124

public_class_method def self.asm_to_opcodes(opts = {})
  asm = opts[:asm]
  arch = opts[:arch] ||= PWN::Plugins::DetectOS.arch
  endian = opts[:endian] ||= PWN::Plugins::DetectOS.endian
  endian = endian.to_sym if opts[:endian]

  asm_tmp = Tempfile.new('pwn_asm')

  raise 'ERROR: asm parameter is required.' if asm.nil?

  case arch.to_s.downcase
  when 'i386', 'i686', 'x86'
    arch_obj = Metasm::Ia32.new(endian)
  when 'amd64', 'x86_64'
    arch_obj = Metasm::X86_64.new(endian)
  when 'arc'
    arch_obj = Metasm::ARC.new(endian)
  when 'armv4l', 'armv4b', 'armv5l', 'armv5b', 'armv6l', 'armv6b', 'armv7b', 'armv7l', 'arm', 'armhf'
    arch_obj = Metasm::ARM.new(endian)
  when 'aarch64', 'arm64'
    arch_obj = Metasm::ARM64.new(endian)
  when 'bpf'
    arch_obj = Metasm::BPF.new(endian)
  when 'cy16'
    arch_obj = Metasm::CY16.new(endian)
  when 'dalvik'
    arch_obj = Metasm::Dalvik.new(endian)
  when 'ebpf'
    arch_obj = Metasm::EBPF.new(endian)
  when 'mcs51'
    arch_obj = Metasm::MCS51.new(endian)
  when 'mips'
    arch_obj = Metasm::MIPS.new(endian)
  when 'mips64'
    arch_obj = Metasm::MIPS64.new(endian)
  when 'msp430'
    arch_obj = Metasm::MSP430.new(endian)
  when 'openrisc'
    arch_obj = Metasm::OpenRisc.new(endian)
  when 'ppc'
    arch_obj = Metasm::PPC.new(endian)
  when 'sh4'
    arch_obj = Metasm::SH4.new(endian)
  when 'st20'
    arch_obj = Metasm::ST20.new(endian)
  when 'webasm'
    arch_obj = Metasm::WebAsm.new(endian)
  when 'z80'
    arch_obj = Metasm::Z80.new(endian)
  else
    raise "Unsupported architecture: #{arch}"
  end

  opcodes = Metasm::Shellcode.assemble(arch_obj, asm).encode_string
  hex_encoded_opcodes = opcodes.bytes.map { |b| format('\x%02x', b) }.join

  "\n#{hex_encoded_opcodes}\n"
rescue Metasm::ParseError
  puts "Invalid assembly instruction(s) provided:\n#{asm}"
  # Should we try to call opcode_to_asm here or just raise the error?
rescue StandardError => e
  raise e
end

.authors ⇒ Object

Author(s)

0day Inc. <[email protected]>



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# File 'lib/pwn/plugins/assembly.rb', line 232

public_class_method def self.authors
  "AUTHOR(S):
    0day Inc. <[email protected]>
  "
end

.help ⇒ Object

Display Usage for this Module



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# File 'lib/pwn/plugins/assembly.rb', line 240

public_class_method def self.help
  puts "USAGE:
    #{self}.opcodes_to_asm(
      opcodes: 'required - hex escaped opcode(s) (e.g. \"\\x90\\x90\\x90\")',
      opcodes_always_string_obj: 'optional - always interpret opcodes passed in as a string object (defaults to false)',
      arch: 'optional - architecture returned from objdump --info (defaults to PWN::Plugins::DetectOS.arch)',
      endian: 'optional - endianess :big|:little (defaults to system endianess)'
    )

    #{self}.asm_to_opcodes(
      asm: 'required - assembly instruction(s) (e.g. 'nop\nnop\nnop\njmp rsp\n)',
      arch: 'optional - architecture returned from objdump --info (defaults to PWN::Plugins::DetectOS.arch)',
      endian: 'optional - endianess :big|:little (defaults to system endianess)'
    )

    #{self}.list_supported_archs

    #{self}.authors
  "
end

.list_supported_archs ⇒ Object

Supported Method Parameters

PWN::Plugins::Assembly.list_archs



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# File 'lib/pwn/plugins/assembly.rb', line 191

public_class_method def self.list_supported_archs
  [
    { name: 'i386', endian: 'little' },
    { name: 'i686', endian: 'little' },
    { name: 'x86', endian: 'little' },
    { name: 'amd64', endian: 'little' },
    { name: 'x86_64', endian: 'little' },
    { name: 'arc', endian: 'little' },
    { name: 'armv4l', endian: 'little' },
    { name: 'armv4b', endian: 'big' },
    { name: 'armv5l', endian: 'little' },
    { name: 'armv5b', endian: 'big' },
    { name: 'armv6l', endian: 'little' },
    { name: 'armv6b', endian: 'big' },
    { name: 'armv7b', endian: 'big' },
    { name: 'armv7l', endian: 'little' },
    { name: 'arm', endian: 'little' },
    { name: 'armhf', endian: 'little' },
    { name: 'aarch64', endian: 'little' },
    { name: 'arm64', endian: 'little' },
    { name: 'bpf', endian: 'little' },
    { name: 'cy16', endian: 'little' },
    { name: 'dalvik', endian: 'little' },
    { name: 'ebpf', endian: 'little' },
    { name: 'mcs51', endian: 'little' },
    { name: 'mips', endian: 'little' },
    { name: 'mips64', endian: 'little' },
    { name: 'msp430', endian: 'little' },
    { name: 'openrisc', endian: 'little' },
    { name: 'ppc', endian: 'little' },
    { name: 'sh4', endian: 'little' },
    { name: 'st20', endian: 'little' },
    { name: 'webasm', endian: 'little' },
    { name: 'z80', endian: 'little' }
  ]
rescue StandardError => e
  raise e
end

.opcodes_to_asm(opts = {}) ⇒ Object

Supported Method Parameters

PWN::Plugins::Assembly.opcodes_to_asm(

opcodes: 'required - hex escaped opcode(s) (e.g. "\x90\x90\x90")',
opcodes_always_string_obj: 'optional - always interpret opcodes passed in as a string object (defaults to false)',
arch: 'optional - architecture returned from objdump --info (defaults to PWN::Plugins::DetectOS.arch)',
endian: 'optional - endianess :big|:little (defaults to current system endianess)'

)



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# File 'lib/pwn/plugins/assembly.rb', line 19

public_class_method def self.opcodes_to_asm(opts = {})
  opcodes = opts[:opcodes]
  opcodes_always_string_obj = opts[:opcodes_always_string_obj] ||= false
  arch = opts[:arch] ||= PWN::Plugins::DetectOS.arch
  endian = opts[:endian] ||= PWN::Plugins::DetectOS.endian
  endian = endian.to_sym if opts[:endian]

  raise 'ERROR: opcodes parameter is required.' if opcodes.nil?

  case arch.to_s.downcase
  when 'i386', 'i686', 'x86'
    arch_obj = Metasm::Ia32.new(endian)
  when 'amd64', 'x86_64'
    arch_obj = Metasm::X86_64.new(endian)
  when 'arc'
    arch_obj = Metasm::ARC.new(endian)
  when 'armv4l', 'armv4b', 'armv5l', 'armv5b', 'armv6l', 'armv6b', 'armv7b', 'armv7l', 'arm', 'armhf'
    arch_obj = Metasm::ARM.new(endian)
  when 'aarch64', 'arm64'
    arch_obj = Metasm::ARM64.new(endian)
  when 'bpf'
    arch_obj = Metasm::BPF.new(endian)
  when 'cy16'
    arch_obj = Metasm::CY16.new(endian)
  when 'dalvik'
    arch_obj = Metasm::Dalvik.new(endian)
  when 'ebpf'
    arch_obj = Metasm::EBPF.new(endian)
  when 'mcs51'
    arch_obj = Metasm::MCS51.new(endian)
  when 'mips'
    arch_obj = Metasm::MIPS.new(endian)
  when 'mips64'
    arch_obj = Metasm::MIPS64.new(endian)
  when 'msp430'
    arch_obj = Metasm::MSP430.new(endian)
  when 'openrisc'
    arch_obj = Metasm::OpenRisc.new(endian)
  when 'ppc'
    arch_obj = Metasm::PPC.new(endian)
  when 'sh4'
    arch_obj = Metasm::SH4.new(endian)
  when 'st20'
    arch_obj = Metasm::ST20.new(endian)
  when 'webasm'
    arch_obj = Metasm::WebAsm.new(endian)
  when 'z80'
    arch_obj = Metasm::Z80.new(endian)
  else
    raise "Unsupported architecture: #{arch}"
  end

  # TOOD: Still needs a fix if opcodes are passed in as:
  # '\x90\x90\x90' (not to be confused w/ "\x90\x90\x90")
  # '909090'
  opcodes_orig_len = opcodes.length
  opcodes = opcodes.join(',') if opcodes.is_a?(Array)
  # puts opcodes.inspect
  opcodes = CGI.escape(opcodes)
  # puts opcodes.inspect
  # known to work (when method is called directly) with:
  # 'ffe4'
  # 'ff,e4'
  # 'ff e4'
  # "ff,e4"
  # "ff e4"
  # ['ff', 'e4']
  # ["ff", "e4"]
  # '\xff\xe4'
  # "\xff\xe4"
  # "'ff', 'e4'"
  # '"ff", "e4"'
  # only known to work in pwn REPL driver with:
  # ffe4
  # ff e4
  # puts opcodes.inspect
  #  More stripping if passed in via pwn REPL driver
  # if opcodes_always_string_obj
  # end

  opcodes.delete!('%5B')
  opcodes.delete!('%5D')
  opcodes.delete!('%5Cx')
  opcodes.delete!('%2C')
  opcodes.delete!('%22')
  opcodes.delete!('%27')
  opcodes.delete!('+')
  opcodes.delete!('%')

  # puts opcodes.inspect
  opcodes = [opcodes].pack('H*')
  # puts opcodes.inspect

  Metasm::Shellcode.disassemble(arch_obj, opcodes).to_s.squeeze("\n")
rescue StandardError => e
  raise e
end