What happens when I convert to Delphi AES256 and the value is wrong?-CodePudding

I'm sorry that I posted too many questions on the same topic. I've been searching Google all day to solve this alone, but I couldn't solve it with my own ability. I am thinking about it, and I am posting the last question.

====Other Developer Settings====
Encryption key value: 1q2w3e4r
AES encryption settings)
Cipher mode: CBC
Key size = 16 bytes
Block size = 16 bytes
Ding pk : PKCS7

the right value ???????-> AES256-CBC-PKCS7 Value: gRI2SaW/HMknK/5tuJ2S9Q==

My value ???????-> AES256-CBC-PKCS7 Value: A8MAUAUIDpQcNEKNFqZDA==

I don't know why it's different when the results come up as above. The number of characters is the same, but the encrypted value is incorrect and cannot be approved. AES256 encryption is successful, but what is wrong? ToT

function EncryptData(Data: string; AKey: AnsiString; AIv: AnsiString): string;
var
  cipher: TDCP_rijndael;
  key, iv, src, dest, b64: TBytes;
  index, slen, bsize, pad: integer;
begin
  //key := Base64DecodeBytes(TEncoding.UTF8.GetBytes(AKey));
  //iv := Base64DecodeBytes(TEncoding.UTF8.GetBytes(AIv));
  key := TEncoding.UTF8.GetBytes('1q2w3e4r1q2w3e4r1q2w3e4r1q2w3e4r');
  iv := TEncoding.UTF8.GetBytes('1q2w3e4r1q2w3e4r');

  src := TEncoding.UTF8.GetBytes(Data);

  cipher := TDCP_rijndael.Create(nil);
  try
    cipher.CipherMode := cmCBC;
    // Add padding.
    // Resize the Value array to make it a multiple of the block length.
    // If it's already an exact multiple then add a full block of padding.
    slen := Length(src);
    bsize := (cipher.BlockSize div 8);
    pad := bsize - (slen mod bsize);
    Inc(slen, pad);
    SetLength(src, slen);
    for index := pad downto 1 do
    begin
      src[slen - index] := pad;
    end;

    SetLength(dest, slen);
    cipher.Init(key[0], 256, @iv[0]); // DCP uses key size in BITS not BYTES
    cipher.Encrypt(src[0], dest[0], slen);

    b64 := Base64EncodeBytes(dest);
    result := TEncoding.Default.GetString(b64);
  finally
    cipher.Free;
  end;
end;

function Base64EncodeBytes(Input: TBytes): TBytes;
var
  ilen: integer;
begin
  ilen := Length(Input);
  SetLength(result, ((ilen   2) div 3) * 4);
  Base64Encode(@Input[0], @result[0], ilen);
end;

procedure TForm1.Button9Click(Sender: TObject);
begin
Edit2.Text := EncryptData(EditCarNumber.Text,'','');
 end;

CodePudding user response：

I solved it with my senior developer.

If anyone is looking for it, I hope it helps. Please refer to the question for setting

function EncryptData(Data: string; AKey: AnsiString; AIv: AnsiString): string;
var
  cipher: TDCP_rijndael;
  key, iv, src, dest, b64: TBytes;
  index, slen, bsize, pad: integer;
begin
  key := TEncoding.UTF8.GetBytes('1q2w3e4r');       //Specify key value
  iv := TEncoding.UTF8.GetBytes('1q2w3e4r');        //Specify iv value

  SetLength(key, 16);                               //Set the key value to 16 bytes
  SetLength(iv, 16);                                //Set the iv value to 16 bytes

  src := TEncoding.UTF8.GetBytes(Data);

  cipher := TDCP_rijndael.Create(nil);
  try
    cipher.CipherMode := cmCBC;
    slen := Length(src);
    bsize := (cipher.BlockSize div 8);             //The block size is 8byte

    pad := bsize - (slen mod bsize);
    Inc(slen, pad);
    SetLength(src, slen);
    for index := pad downto 1 do
    begin
      src[slen - index] := pad;
    end;

    SetLength(dest, slen);
    cipher.Init(key[0], 128, @iv[0]);             //key[0], 128bit, @iv[0]take as
    cipher.Encrypt(src[0], dest[0], slen);

    b64 := Base64EncodeBytes(dest);              //Encoding received values to Base64 values
    result := TEncoding.Default.GetString(b64);  //Get b64 value by string.
  finally
    cipher.Free;
  end;
end;