@Test
    @DisplayName("getServerEncryptionKey returns expected bytes")
    void serverEncryptionKey_variants() {
        byte[] key = new byte[] { 1, 2, 3 };
        when(transport.getServerEncryptionKey()).thenReturn(key);
        assertArrayEquals(key, transport.getServerEncryptionKey());
        verify(transport).getServerEncryptionKey();

        // Empty array
        byte[] empty = new byte[0];

    }

    @Override
    public boolean isSigningEnforced() throws SmbException {
        return delegate.isSigningEnforced();
    }

    @Override
    public byte[] getServerEncryptionKey() {
        return delegate.getServerEncryptionKey();
    }

    @Override
    public SmbSession getSmbSession(CIFSContext ctx) {
        return delegate.getSmbSession(ctx);
    }

    @Override

        setField(transport, "negotiated", smb1);
        assertArrayEquals(new byte[] { 1, 2, 3 }, transport.getServerEncryptionKey());

        // SMB2 negotiation never exposes key via this API
        setField(transport, "negotiated", new Smb2NegotiateResponse(cfg));
        assertNull(transport.getServerEncryptionKey());
    }

    @Test
    @DisplayName("Signing enforced/optional adhere to flags and negotiation")

    boolean isSigningEnforced() throws SmbException;

    /**
     * Gets the server's encryption key for authentication.
     *
     * @return the encryption key used by the server
     */
    byte[] getServerEncryptionKey();

    /**
     * Gets or creates an SMB session for the given context.
     *
     * @param ctx the CIFS context
     * @return session
     */
    SmbSession getSmbSession(CIFSContext ctx);

        when(mockTransport.getContext()).thenReturn(mockContext);
        when(mockContext.getConfig()).thenReturn(mockConfig);
        when(mockConfig.getLanManCompatibility()).thenReturn(3);
        when(mockTransport.getServerEncryptionKey()).thenThrow(new RuntimeException("Test exception"));

        assertThrows(SmbException.class, () -> new SMB1SigningDigest(mockTransport, mockAuth));
    }

    @Test

        when(mockTransport.unwrap(SmbTransportInternal.class)).thenReturn(internal);
        when(internal.ensureConnected()).thenReturn(true);
        when(internal.getServerEncryptionKey()).thenReturn(expectedKey);

        doReturn(mockTransport).when(poolSpy).getSmbTransport(eq(ctx), any(Address.class), anyInt(), eq(false), anyBoolean());

        // When: Get challenge

        this.digest = Crypto.getMD5();
        try {
            final byte[] serverEncryptionKey = transport.getServerEncryptionKey();
            switch (transport.getContext().getConfig().getLanManCompatibility()) {
            case 0:
            case 1:
            case 2:
                this.macSigningKey = new byte[40];

                    ssn.treeConnectLogon();
                }
            }
            return new NtlmChallenge(trans.getServerEncryptionKey(), dc);
        } catch (final SmbException e) {
            throw e;
        } catch (final IOException e) {
            throw new SmbException("Connection failed", e);
        }
    }

    /**

                .unwrap(SmbTransportInternal.class)) {
            trans.ensureConnected();
            return trans.getServerEncryptionKey();
        } catch (final SmbException e) {
            throw e;
        } catch (final IOException e) {
            throw new SmbException("Connection failed", e);
        }
    }

    @Override

    public SmbTransportImpl acquire() {
        return (SmbTransportImpl) super.acquire();
    }

    /**
     * @return the server's encryption key
     */
    @Override
    public byte[] getServerEncryptionKey() {
        if (this.negotiated == null) {
            return null;
        }

        if (this.negotiated instanceof SmbComNegotiateResponse) {