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<?php $allowed_chars = 'a\-z 0\-9~%\.\:_\-'; $str = 'renewal'; if ( ! preg_match("/^[".$allowed_chars."]+$/i", $str)){ echo "Unallowed!!!!"; }else{ echo "Looks fine"; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 10, Position 2 = 12
Branch analysis from position: 10
1 jumps found. (Code = 42) Position 1 = 13
Branch analysis from position: 13
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 12
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/PmWuc
function name:  (null)
number of ops:  14
compiled vars:  !0 = $allowed_chars, !1 = $str
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, 'a%5C-z+0%5C-9%7E%25%5C.%5C%3A_%5C-'
    3     1        ASSIGN                                                   !1, 'renewal'
    4     2        INIT_FCALL                                               'preg_match'
          3        CONCAT                                           ~4      '%2F%5E%5B', !0
          4        CONCAT                                           ~5      ~4, '%5D%2B%24%2Fi'
          5        SEND_VAL                                                 ~5
          6        SEND_VAR                                                 !1
          7        DO_ICALL                                         $6      
          8        BOOL_NOT                                         ~7      $6
          9      > JMPZ                                                     ~7, ->12
    5    10    >   ECHO                                                     'Unallowed%21%21%21%21'
         11      > JMP                                                      ->13
    7    12    >   ECHO                                                     'Looks+fine'
    8    13    > > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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