assertEquals("errors.password_no_lowercase", systemHelper.validatePassword("PASSWORD1!"));
        assertEquals("errors.password_no_digit", systemHelper.validatePassword("Password!"));
        assertEquals("errors.password_no_special_char", systemHelper.validatePassword("Password1"));
        assertEquals("", systemHelper.validatePassword("Password1!"));

        // Test the method directly
        char[] password1 = "testpassword".toCharArray();
        char[] password2 = "testpassword".toCharArray();
        char[] password3 = "testpassworX".toCharArray();

        Boolean result1 = (Boolean) constantTimeMethod.invoke(null, password1, password2);
        Boolean result2 = (Boolean) constantTimeMethod.invoke(null, password1, password3);

        byte[] actual = NtlmUtil.getNTHash(password);

        // Assert
        assertArrayEquals(expected, actual, "NT hash must match known test vector");
    }

    @Test
    @DisplayName("getNTHash: verify different passwords produce different hashes")
    void testGetNTHash_differentPasswords() {
        // Arrange
        String password1 = "password";
        String password2 = "Password";

        // Act

        NtlmPasswordAuthenticator auth2 = new NtlmPasswordAuthenticator("DOMAIN", "user", password2);
        NtlmPasswordAuthenticator auth3 = new NtlmPasswordAuthenticator("DOMAIN", "user", password3);

        // Test equality with same password
        assertEquals(auth1, auth2);
        assertEquals(auth1.hashCode(), auth2.hashCode());

        // Test inequality with different password

# OAuth2 mit Passwort (und Hashing), Bearer mit JWT-Tokens { #oauth2-with-password-and-hashing-bearer-with-jwt-tokens }

Da wir nun über den gesamten Sicherheitsablauf verfügen, machen wir die Anwendung tatsächlich sicher, indem wir <abbr title="JSON Web Tokens">JWT</abbr>-Tokens und sicheres Passwort-Hashing verwenden.

Diesen Code können Sie tatsächlich in Ihrer Anwendung verwenden, die Passwort-Hashes in Ihrer Datenbank speichern, usw.

Nunca deberías guardar passwords en texto plano, así que, usaremos el sistema de hash de passwords (falso).

Si los passwords no coinciden, devolvemos el mismo error.

#### Hashing de passwords { #password-hashing }

"Hacer hash" significa: convertir algún contenido (un password en este caso) en una secuencia de bytes (solo un string) que parece un galimatías.

# Einfaches OAuth2 mit Password und Bearer { #simple-oauth2-with-password-and-bearer }

Lassen Sie uns nun auf dem vorherigen Kapitel aufbauen und die fehlenden Teile hinzufügen, um einen vollständigen Sicherheits-Flow zu erhalten.

## `username` und `password` entgegennehmen { #get-the-username-and-password }

Wir werden **FastAPIs** Sicherheits-Werkzeuge verwenden, um den `username` und das `password` entgegenzunehmen.

///

## Password hashing { #password-hashing }

"Hashing" means converting some content (a password in this case) into a sequence of bytes (just a string) that looks like gibberish.

Whenever you pass exactly the same content (exactly the same password) you get exactly the same gibberish.

But you cannot convert from the gibberish back to the password.

### Why use password hashing { #why-use-password-hashing }

        assertTrue("Result should contain password={cipher}, but was: " + result, result.contains("password={cipher}"));

        // Test with empty encryption target
        value = "password=";
        result = ParameterUtil.encrypt(value);
        assertTrue(result.contains("password={cipher}"));

        // Test with only whitespace value
        value = "password=   ";
        result = ParameterUtil.encrypt(value);

            throw new IllegalArgumentException("Master password cannot be null or empty");
        }

        // Generate salt for key derivation
        this.salt = new byte[SALT_SIZE];
        secureRandom.nextBytes(this.salt);

        // Derive master key from password
        this.masterKey = deriveKey(masterPassword, salt);

        // Clear the master password after use
        Arrays.fill(masterPassword, '\0');
    }