*&---------------------------------------------------------------------*
*& Report  ZBC_SOLMAN_KEY
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*
report zbc_solman_key.

selection-screen begin of block sele1 with frame.
parameters:
  sid(3),
  sysno(2),
  server(15).
selection-screen end of block sele1.

selection-screen begin of block sele2 with frame.
parameters:
  key(10).
selection-screen end of block sele2.

at selection-screen.

  if sid    is not initial and
     sysno  is not initial and
     server is not initial.
    perform get_sp_value using sid sysno server changing key.
  else.
    clear key.
  endif.

*&---------------------------------------------------------------------*
*&      Form  get_sp_value
*&---------------------------------------------------------------------*
*       text
*----------------------------------------------------------------------*
*      -->P_PF_SID  text
*      -->P_PF_SYSNO  text
*      -->P_PF_SERVER  text
*      <--P_PF_VALUE  text
*----------------------------------------------------------------------*
form get_sp_value using    p_pf_sid
                           p_pf_sysno
                           p_pf_server
                  changing p_pf_value.

  constants:
    lc_part_len          type i value 5,
    lc_pw_len            type i value 10,
    lc_allowed_chars(38) type c value '-0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_'.


  data: lf_string(20)        type c,
        lf_key               type i,
        lf_part(lc_part_len) type c,
        lf_finalf(lc_pw_len) type c,
        lf_finalx            type xstring,
        lf_xbuffer           type xstring,
        lf_opf(10)           type c,
        lf_langu             like sy-langu,
        lf_subrc             like sy-subrc,
        lf_len               type i,
        lo_conv_to_x         type ref to cl_abap_conv_out_ce.

  clear: lf_string, lf_finalx, lf_opf.

  concatenate p_pf_sid p_pf_sysno p_pf_server into lf_string.

* Large letters only
  translate lf_string to upper case.

  lf_langu = sy-langu.
  set locale language 'E'.
  lo_conv_to_x = cl_abap_conv_out_ce=>create( encoding = '1100' ).
  lf_len = strlen( lf_string ).

  if lf_string(lf_len) cn lc_allowed_chars.

  else.

* Fold the input string to a lc_part_len long string
    while lf_len > 0.
      lf_part = lf_string(lc_part_len).
      shift lf_string by lc_part_len places.
      lf_len = strlen( lf_string ).
      call method lo_conv_to_x->reset.
      call method lo_conv_to_x->write( data = lf_part n = -1 ).
      lf_xbuffer = lo_conv_to_x->get_buffer( ).
      lf_finalx = lf_finalx bit-xor lf_xbuffer.
    endwhile.

    lf_key = 12.

    perform scramble using    lf_finalx
                              lf_key
                              lc_part_len
                     changing lf_finalf
                              lf_subrc.

    if not lf_finalf is initial.
      p_pf_value = lf_finalf.
    else.
      clear p_pf_value.
    endif.

  endif.
endform.                    " get_sp_value
*&---------------------------------------------------------------------*
*&      Form  scramble
*&---------------------------------------------------------------------*
*       text
*----------------------------------------------------------------------*
*      -->P_LF_FINALX  text
*      -->P_LF_KEY  text
*      -->P_LC_PART_LEN  text
*      <--P_LF_finalf  text
*      <--P_LF_SUBRC  text
*----------------------------------------------------------------------*
form scramble using    iv_xstring type xstring
                       iv_key type i
                       iv_src_len type i
              changing lf_finalf
                       lf_subrc like sy-subrc.

  constants: lc_max_len    type i value 20,
             lc_mask(4)    type x value '0000003F',
             lc_random(64) type x value
                      'F0ED53B83244F1F876C67959FD4F13A2' &
                      'C15195EC5483C234774943A27DE26596' &
                      '5E5398789A17A33CD383A8B829FBDCA5' &
                      '55D702778413ACDDF9B83116610E6DFA'.

  data: lv_key_index(4)  type x,
        lv_rand_index(4) type x,
        lv_xkey(4)       type x,
        lv_xkey_shl_1(4) type x,
        lv_xkey_shr_5(4) type x,
        lv_scramble_byte type x,
        lv_dest(lc_max_len) type x,
        lv_index         type i,
        lv_len           type i.

  clear lf_subrc.

  if iv_src_len eq 0. exit. endif.
  lv_len = xstrlen( iv_xstring ).
  if iv_src_len gt lc_max_len or
     iv_src_len gt lv_len.
    lf_subrc = 2.
    exit.
  endif.

  lv_xkey       = iv_key.
  lv_xkey_shl_1 = iv_key * 2.
  lv_xkey_shr_5 = iv_key div 32.
  lv_rand_index = lv_xkey bit-xor lv_xkey_shr_5 bit-xor lv_xkey_shl_1.
  lv_rand_index = lv_rand_index bit-and lc_mask.

  lv_index = 0.
  do iv_src_len times.
    catch system-exceptions compute_int_times_overflow = 1.
      lv_key_index = ( iv_key * lv_index * lv_index ) - lv_index.
    endcatch.
    if sy-subrc <> 0.
      lf_subrc = 1.
      exit.
    endif.
    lv_scramble_byte = lc_random+lv_rand_index(1) bit-xor
                       lv_key_index+3(1).
    lv_dest+lv_index(1) = iv_xstring+lv_index(1) bit-xor
                          lv_scramble_byte.
    lv_index = lv_index + 1.
    lv_rand_index = lv_rand_index + 1.
    lv_rand_index = lv_rand_index bit-and lc_mask.
  enddo.
  if lf_subrc <> 0.
    exit.
  endif.

  write lv_dest(iv_src_len) to lf_finalf.

endform.                    " scramble