throw new RuntimeException("Failed to create Mac instance", e);
            }

            mac.update(data, offset, length);
            final byte[] sig = mac.doFinal();
            System.arraycopy(sig, 0, data, offset + SIGNATURE_OFFSET, SIGNATURE_LENGTH);
        } finally {
            this.signingLock.unlock();
        }
    }

    /**
     *
     * {@inheritDoc}
     *

        bufferIndex += 8;
        bufferIndex += 8;

        final int nameLen = SMBUtil.readInt4(buffer, bufferIndex);
        bufferIndex += 4;
        final byte[] nameBytes = new byte[nameLen];
        System.arraycopy(buffer, bufferIndex, nameBytes, 0, nameBytes.length);
        bufferIndex += nameLen;
        this.fileName = new String(nameBytes, StandardCharsets.UTF_16LE);
        return bufferIndex - start;
    }

    /**

            bytesToRecover -= toEvict.hpackSize
            dynamicTableByteCount -= toEvict.hpackSize
            headerCount--
            entriesToEvict++
            j--
          }
          System.arraycopy(
            dynamicTable,
            nextHeaderIndex + 1,
            dynamicTable,
            nextHeaderIndex + 1 + entriesToEvict,
            headerCount,
          )

        final int start = bufferIndex;

        if ((server.capabilities & CAP_EXTENDED_SECURITY) == 0) {
            server.encryptionKey = new byte[server.encryptionKeyLength];
            System.arraycopy(buffer, bufferIndex, server.encryptionKey, 0, server.encryptionKeyLength);
            bufferIndex += server.encryptionKeyLength;
            if (byteCount > server.encryptionKeyLength) {
                int len = 0;

            System.arraycopy(buffer, bufferIndex, txn_buf, bufParameterStart + parameterDisplacement, parameterCount);
            bufferIndex += parameterCount;
        }
        if (dataCount > 0) {
            bufferIndex += pad1 = dataOffset - (bufferIndex - headerStart);
            System.arraycopy(buffer, bufferIndex, txn_buf, bufDataStart + dataDisplacement, dataCount);

        if ((this.server.scapabilities & SmbConstants.CAP_EXTENDED_SECURITY) == 0) {
            this.server.encryptionKey = new byte[this.server.encryptionKeyLength];
            System.arraycopy(buffer, bufferIndex, this.server.encryptionKey, 0, this.server.encryptionKeyLength);
            bufferIndex += this.server.encryptionKeyLength;
            if (this.byteCount > this.server.encryptionKeyLength) {

        // Verify output buffer length
        assertEquals(8192, SMBUtil.readInt4(buffer, offset + 4));

        // Verify file ID
        byte[] readFileId = new byte[16];
        System.arraycopy(buffer, offset + 8, readFileId, 0, 16);
        assertArrayEquals(testFileId, readFileId);

        // Verify completion filter

        // Verify description
        byte[] descr = NetServerEnum2.DESCR[0].getBytes("ASCII");
        byte[] writtenDescr = new byte[descr.length];
        System.arraycopy(dst, 2, writtenDescr, 0, descr.length);
        assertArrayEquals(descr, writtenDescr);

        int currentIndex = 2 + descr.length;
        // Verify level (0x0001)

        writeInt4(buffer, offset + 12, 16);  // DataLength
        
        // Name
        System.arraycopy(getName().getBytes(), 0, buffer, offset + 16, nameLen);
        
        // Data (16-byte file ID)
        int dataOffset = offset + 16 + nameLen;
        dataOffset = (dataOffset + 7) & ~7;  // 8-byte alignment
        System.arraycopy(fileId, 0, buffer, dataOffset, 16);
    }
}
```

### 4.5 Persistent Handle Manager

        // Verify context name
        byte[] nameBytes = new byte[4];
        System.arraycopy(buffer, 16, nameBytes, 0, 4);
        assertEquals("DLse", new String(nameBytes));

        // Verify lease key (first 16 bytes of data)
        byte[] leaseKeyBytes = new byte[16];
        System.arraycopy(buffer, 24, leaseKeyBytes, 0, 16);
        assertArrayEquals(key.getKey(), leaseKeyBytes);