This code was published by VMware on their website at https://customerconnect.vmware.com/downloads/details?productId=23&downloadGroup=SERVER-SCSI-OS The intro there says: This open source software is licensed under the terms of various open source license agreements included with the materials relating to the open source software. Copyrights in the open source software are held by the copyright holders indicated in the copyright notices in the open source files. You may download this software free of charge. The source files indicate they are GPL licenced, so we're ok to include it in ReactOS.