Enkele dagen geleden is de nieuwe halfjaarlijkse release van OpenBSD uitgekomen. Op deze pagina is een uitgebreide lijst van ftp- en http-downloadlocaties te vinden. OpenBSD stamt af van de originele Berkeley Software Distribution en heeft als kenmerk dat de ontwikkelaars alleen opensourcesoftware willen gebruiken. Verder staat het besturingssysteem bekend om zijn uitstekende documentatie en veiligheid. Uitgebreide releasenotes kunnen op deze pagina worden gevonden; hieronder is een overzicht te vinden van de belangrijkste verbeteringen:
BSD Release: OpenBSD 6.4
The project has released OpenBSD 6.4 which includes many driver improvements, a feature which allows OpenSSH's configuration files to use service names instead of port numbers, and the Clang compiler will now replace some risky ROP instructions with safe alternatives.
Perhaps the most interesting feature is the unveil() system call which allows applications to sandbox themselves, blocking their own access to the file system. This is especially useful for programs which operate on unknown data which may try to exploit or crash the application: "New unveil(2) system call to restrict file system access of the calling process to the specified files and directories. It is most powerful when properly combined with privilege separation and pledge(2)."
Other security improvements include: "Implemented MAP_STACK option for mmap(2); new RETGUARD security mechanism on amd64 and arm64 - use per-function random cookies to protect access to function return instructions, making them harder to use in ROP gadgets...."