Class: SeccompTools::Instruction::JMP

Inherits:
Base
  • Object
show all
Defined in:
lib/seccomp-tools/instruction/jmp.rb

Overview

Instruction jmp.

Constant Summary

Constants included from Const::BPF

Const::BPF::ACTION, Const::BPF::COMMAND, Const::BPF::JMP, Const::BPF::MISCOP, Const::BPF::MODE, Const::BPF::OP, Const::BPF::PR_SET_SECCOMP, Const::BPF::SECCOMP_MODE_FILTER, Const::BPF::SECCOMP_RET_ACTION_FULL, Const::BPF::SECCOMP_RET_DATA, Const::BPF::SECCOMP_SET_MODE_FILTER, Const::BPF::SIZEOF_SECCOMP_DATA, Const::BPF::SRC

Instance Method Summary collapse

Methods inherited from Base

#initialize, #invalid

Constructor Details

This class inherits a constructor from SeccompTools::Instruction::Base

Instance Method Details

#branch(context) ⇒ Array<(Integer, Context)>

See Base#branch.

Parameters:

  • context (Context) —

    Current context.

Returns:

  • (Array<(Integer, Context)>) 


36
37
38
39
40
41
42
 
# File 'lib/seccomp-tools/instruction/jmp.rb', line 36

def branch(context)
  return [[at(k), context]] if jop == :none
  return [[at(jt), context]] if jt == jf
  return [[at(jt), context.dup.eql!(src)], [at(jf), context]] if jop == :==

  [[at(jt), context], [at(jf), context]]
end

#decompile ⇒ Object

Decompile instruction.



11
12
13
14
15
16
17
18
19
20
21
22
 
# File 'lib/seccomp-tools/instruction/jmp.rb', line 11

def decompile
  return goto(k) if jop == :none
  # if jt == 0 && jf == 0 => no-op # should not happen
  # jt == 0 => if(!) goto jf;
  # jf == 0 => if() goto jt;
  # otherwise => if () goto jt; else goto jf;
  return '/* no-op */' if jt.zero? && jf.zero?
  return goto(jt) if jt == jf
  return if_str(neg: true) + goto(jf) if jt.zero?

  if_str + goto(jt) + (jf.zero? ? '' : " else #{goto(jf)}")
end

#symbolize ⇒ [:cmp, Symbol, (:x, Integer), Integer, Integer], [:jmp, Integer]

See Base#symbolize.

Returns:

  • ([:cmp, Symbol, (:x, Integer), Integer, Integer], [:jmp, Integer]) 


26
27
28
29
30
 
# File 'lib/seccomp-tools/instruction/jmp.rb', line 26

def symbolize
  return [:jmp, k] if jop == :none

  [:cmp, jop, src, jt, jf]
end