DcerpcPipeHandle handle = createMockedDcerpcPipeHandle();
            byte[] expectedKey = "sessionKey".getBytes();
            when(mockSmbPipeHandleInternal.getSessionKey()).thenReturn(expectedKey);
            assertArrayEquals(expectedKey, handle.getSessionKey());
        }

        @Test
        @DisplayName("Should propagate CIFSException when getting session key")

        assertNull(session.getSessionKey());
        verify(session, times(3)).getSessionKey();
    }

    // Error propagation: getSessionKey throws CIFSException
    @Test
    @DisplayName("getSessionKey throws CIFSException on failure")
    void getSessionKey_throws() throws CIFSException {
        doThrow(new CIFSException("session key failure")).when(session).getSessionKey();

    /**
     *
     * {@inheritDoc}
     *
     * @see jcifs.smb.SmbPipeHandleInternal#getSessionKey()
     */
    @Override
    public byte[] getSessionKey() throws CIFSException {
        try (SmbTreeHandleImpl th = ensureTreeConnected(); SmbSessionImpl sess = th.getSession()) {
            return sess.getSessionKey();
        }
    }

    /**
     * {@inheritDoc}
     *

    /**
     * Gets the session key after successful authentication
     *
     * @return the session key or null if not available
     */
    byte[] getSessionKey();

    /**
     * Gets the signing key for SMB2/3
     *
     * @return the signing key or null if not available
     */
    byte[] getSigningKey();

    /**
     * Validates authentication credentials

    }

    @Override
    public String getServerWithDfs() {
        return this.pipe.getLocator().getServerWithDfs();
    }

    @Override
    public byte[] getSessionKey() throws CIFSException {
        return this.handle.getSessionKey();
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.dcerpc.DcerpcHandle#doSendReceiveFragment(byte[], int, int, byte[])
     */
    @Override

        assertTrue(session.isInUse());
    }

    @Test
    @DisplayName("getSessionKey: throws when absent, returns when present")
    void testGetSessionKey() throws Exception {
        SmbSessionImpl session = newSession();

        // Absent key -> CIFSException
        CIFSException noKey = assertThrows(CIFSException.class, session::getSessionKey);
        assertTrue(noKey.getMessage().contains("No session key"));

    }

    @Test
    @DisplayName("getSessionKey fetches via tree->session and returns bytes")
    void testGetSessionKey() throws CIFSException {
        when(pipe.ensureTreeConnected()).thenReturn(tree);
        when(tree.acquire()).thenReturn(tree);
        SmbSessionImpl session = mock(SmbSessionImpl.class);
        when(tree.getSession()).thenReturn(session);
        when(session.getSessionKey()).thenReturn(new byte[] { 1, 2, 3 });

    /**
     * Returns the current session key used for signing and encryption.
     *
     * @return the current session key
     * @throws CIFSException if the session key cannot be retrieved
     */
    byte[] getSessionKey() throws CIFSException;

    /**
     * Returns the SMB transport associated with this session.
     *
     * @return the transport for this session
     */
    SmbTransport getTransport();

    /**

            return serverWithDfs;
        }

        @Override
        public CIFSContext getTransportContext() {
            return localTransportContext;
        }

        @Override
        public byte[] getSessionKey() throws CIFSException {
            return sessionKey;
        }

        @Override
        protected void doSendFragment(byte[] buf, int off, int length) throws IOException {

        return masterKey;
    }

    /**
     * Returns the session key.
     *
     * @return A <code>byte[]</code> containing the session key.
     */
    public byte[] getSessionKey() {
        return sessionKey;
    }

    /**
     * Sets the session key.
     *
     * @param sessionKey The session key.
     */
    public void setSessionKey(final byte[] sessionKey) {