// Test that calling initSecContext in an invalid state throws an exception
        when(mockAuth.getDomain()).thenReturn(domain);
        when(mockAuth.getUsername()).thenReturn(username);
        when(mockAuth.getPassword()).thenReturn(password);

        NtlmContext context = new NtlmContext(mockAuth, true);
        context.initSecContext(new byte[0], 0, 0); // state -> 2

        CIFSException ex = assertThrows(CIFSException.class, () -> ctx.initSecContext(new byte[] { firstByte }, 0, 1));
        assertEquals("Invalid token", ex.getMessage());

        // Ensure mechContext was not engaged due to early failure
        verify(this.mechContext, never()).initSecContext(any(), anyInt(), anyInt());
    }

    @Test
    @DisplayName("initSecContext with null buffer and non-zero len throws NPE")

     * @param len length of token data
     * @return result token
     * @throws SmbException if an SMB protocol error occurs
     * @throws CIFSException if a general CIFS error occurs
     */
    byte[] initSecContext(byte[] token, int off, int len) throws CIFSException;

    /**
     * Gets the NetBIOS name of the remote endpoint.
     * @return the name of the remote endpoint
     */
    String getNetbiosName();

    /**

     * @param len length of token data
     * @return the output token bytes
     * @throws SmbException if an error occurs during context initialization
     */
    public byte[] initSecContext(byte[] token, final int offset, final int len) throws SmbException {
        switch (state) {
        case 1:
            final Type1Message msg1 = new Type1Message(ntlmsspFlags, auth.getDomain(), workstation);