// Given
        request.setSessionBinding(true);
        byte[] buffer = new byte[512];
        int headerStart = 50;

        // Encode the full message to set headerStart
        request.encode(buffer, headerStart);

        // Then - verify the body was written correctly
        int bodyOffset = headerStart + Smb2Constants.SMB2_HEADER_LENGTH;

        // Verify structure size (25)

        } else {

            /*
             * Set bufferIndex according to andxOffset
             */

            bufferIndex = this.headerStart + this.andxOffset;

            this.andx.headerStart = this.headerStart;
            this.andx.setCommand(this.andxCommand);
            this.andx.setErrorCode(getErrorCode());
            this.andx.setFlags(getFlags());

        SMBUtil.writeInt4(8, buffer, bufferIndex + 4);

        response = spy(response);
        when(response.getHeaderStart()).thenReturn(headerStart);

        // Write FileInternalInfo data at calculated offset (headerStart + bufferOffset)
        SMBUtil.writeInt8(0xFEDCBA9876543210L, buffer, headerStart + 300);

        int result = response.readBytesWireFormat(buffer, bufferIndex);

        return this.errorContextCount;
    }

    /**
     * Gets the header start position for this message.
     *
     * @return the headerStart
     */
    public final int getHeaderStart() {
        return this.headerStart;
    }

    /**
     * Gets the total length of this message.
     *
     * @return the length
     */
    public final int getLength() {

    @Test
    @DisplayName("readAndXWireFormat applies Snap server workaround (offset 0)")
    void testReadAndXWireFormatSnapWorkaround() {
        DummyAndXBlock block = new DummyAndXBlock();
        block.headerStart = 0;

        byte[] buf = new byte[64];
        buf[0] = 4; // wordCount
        buf[1] = 0x42; // andxCommand
        // andxOffset = 0 triggers workaround -> treat as no andx

            System.arraycopy(this.txn_buf, this.bufParameterOffset, dst, this.headerStart + this.parameterOffset, this.parameterCount);
            end = Math.max(end, this.headerStart + this.parameterOffset + this.parameterCount + this.pad2);
        }

        if (this.dataCount > 0) {
            System.arraycopy(this.txn_buf, this.bufDataOffset, dst, this.headerStart + this.dataOffset, this.dataCount);

    }

    @Override
    int writeParameterWordsWireFormat(final byte[] dst, int dstIndex) {
        final int start = dstIndex;

        dataOffset = dstIndex - headerStart + 26; // 26 = off from here to pad

        pad = (dataOffset - headerStart) % 4;
        pad = pad == 0 ? 0 : 4 - pad;
        dataOffset += pad;

        writeInt2(fid, dst, dstIndex);
        dstIndex += 2;
        writeInt4(offset, dst, dstIndex);

    protected int writeParameterWordsWireFormat(final byte[] dst, int dstIndex) {
        final int start = dstIndex;

        this.dataOffset = dstIndex - this.headerStart + 26; // 26 = off from here to pad

        this.pad = (this.dataOffset - this.headerStart) % 4;
        this.pad = this.pad == 0 ? 0 : 4 - this.pad;
        this.dataOffset += this.pad;

        SMBUtil.writeInt2(this.fid, dst, dstIndex);

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.smb1.smb1;

abstract class SmbComNtTransaction extends SmbComTransaction {

    // relative to headerStart
    private static final int NTT_PRIMARY_SETUP_OFFSET = 69;
    private static final int NTT_SECONDARY_PARAMETER_OFFSET = 51;

    static final int NT_TRANSACT_QUERY_SECURITY_DESC = 6;

    int function;

        if (this.digest != null) {
            this.digest.sign(dst, this.headerStart, this.length, this, this.response);
        }

        return this.length;
    }

    @Override
    public int decode(final byte[] buffer, int bufferIndex) throws SMBProtocolDecodingException {
        final int start = this.headerStart = bufferIndex;

        bufferIndex += readHeaderWireFormat(buffer, bufferIndex);