Method: Rex::Encoder::Alpha2::AlphaUpper.gen_decoder

Defined in:
lib/rex/encoder/alpha2/alpha_upper.rb

.gen_decoder(reg, offset) ⇒ Object 



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# File 'lib/rex/encoder/alpha2/alpha_upper.rb', line 47

def self.gen_decoder(reg, offset)
  decoder =
    gen_decoder_prefix(reg, offset) +
    "V" +           # push esi
    "T" +           # push esp
    "X" +           # pop eax
    "30" +          # xor esi, [eax]
    "V" +           # push esi
    "X" +           # pop eax
    "4A" +          # xor al, 41
    "P" +           # push eax
    "0A3" +         # xor [ecx+33], al
    "H" +           # dec eax
    "H" +           # dec eax
    "0A0" +         # xor [ecx+30], al
    "0AB" +         # xor [ecx+42], al
    "A" +           # inc ecx   <---------------
    "A" +           # inc ecx                   |
    "B" +           # inc edx                   |
    "TAAQ" +        # imul eax, [ecx+41], 10 *  |
    "2AB" +         # xor al [ecx+42]           |
    "2BB" +         # xor al, [edx+42]          |
    "0BB" +         # xor [edx+42], al          |
    "X" +           # pop eax                   |
    "P" +           # push eax                  |
    "8AC" +         # cmp [ecx+43], al          |
    "JJ" +          # jnz * --------------------
    "I"             # first encoded char, fixes the above J

  return decoder
end