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unit racrc;
interface

procedure makecrc32table;
function updatecrc32(c : byte; crc : longint) : longint;
function calccrc(pass1: string) : longint;

implementation

var
    crc32table : array [byte] of longint;
    crcval : longint;
    j      : integer;

procedure makeCRC32table;
var crc : longint;
    i,n : byte;
begin
 for i := 0 to 255 do
   begin
     crc := i;
     for n := 1 to 8 do
       if odd(crc) then
         crc := (crc shr 1) xor $EDB88320
       else
         crc := crc shr 1;
     crc32table[i] := crc;
   end;
end;

function updateCRC32(c : byte; crc : longint) : longint;
begin
 updateCRC32 := crc32table[lo(crc) xor c] xor (crc shr 8);
end;

function calccrc(pass1 : string) : longint;
begin
  makecrc32table;
  crcval := $FFFFFFFF;
  for j := 1 to length(pass1) do
    begin
      crcval := updateCRC32(ord(pass1[j]),crcval);
    end;
    calccrc := crcval;
end;
begin
end.


Use like this:

password := 'REMOTEACCESS';

i := calccrc(password);

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