(Delphi DLL) BCrypt Verify a Password (Check if Password is Correct)

A system that uses BCrypt for storing passwords would not store the actual password, but would instead store the bcrypt hash of the password. When a user presents the password, such as for login, call BCryptVerify to verify the password against the stored bcrypt hash.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Crypt2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
crypt: HCkCrypt2;
storedHash: PWideChar;
password: PWideChar;
passwordValid: Boolean;

begin
// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

crypt := CkCrypt2_Create();

storedHash := '$2a$10$H5kIVktMGzAPKGKNAe9DVu0iwEqfhv/o4MMJ/Dzw/MPy1leOE9NOK';
password := 'mySecretPassword';

passwordValid := CkCrypt2_BCryptVerify(crypt,password,storedHash);
if (passwordValid = True) then
  begin
    Memo1.Lines.Add(password + ' is valid.');
  end
else
  begin
    Memo1.Lines.Add(password + ' is NOT valid.');
  end;

password := 'notAValidPassword';
passwordValid := CkCrypt2_BCryptVerify(crypt,password,storedHash);
if (passwordValid = True) then
  begin
    Memo1.Lines.Add(password + ' is valid.');
  end
else
  begin
    Memo1.Lines.Add(password + ' is NOT valid.');
  end;

// Output should be:

// 	mySecretPassword is valid.
// 	notAValidPassword is NOT valid.

CkCrypt2_Dispose(crypt);

end;