Hackfest Communication
2 HN recommenders · recommended in 5 months, 2015–2022
53:53 · 27K views · Nov 23, 2015
Theo de Raadt presents pledge, a new OpenBSD security mechanism that kills processes which exceed the system calls they declared they need. The talk was given late at night at Hackfest 2015.
HN points to it as the canonical overview of pledge and the ideas behind OpenBSD's exploit mitigations.
6 comments from Hacker News
I thoroughly enjoyed Theo de Raadt recent talk, "Pledge: A new security technology in openbsd". It left me itching to try OpenBSD. "Pledge() is designed as a mitigation rather than a cure-all, de Raadt explains, but it's a mitigation with an interesting approach: a process or application stipulates the system services it needs, and if it steps beyond its boundaries, it's killed." [LINK] Hackfest 2015: Theo de Raadt presented "Pledge: A new security technology in openbsd" video: this video slides: [LINK]
Until we build in security mitigation into the kernel and standard libraries of our operating systems, we will always have failure modes where minor errors in code can result in critical vulnerabilities and privilege escalation. I love what OpenBSD is doing with pledges[0] and hope to see this gain traction in other operating systems. Here is a good overview of Pledge[1] by Theo de Raadt. Unfortunately for Linux ecosystem, the Kernel does not include any standard libs for developers, so this type of security mitigation will take a long time to arrive. But for Unix based operating systems we should expect this much sooner. [0]: [LINK] , [1] this video
I was just listening to Theo's pledge presentation ( this video ) and immediately wondered how this is applied to scripting languages. The github link for Python seems to be a high-level wrapping of the entire Python environment itself. I was wondering if there is a way to surface pledge in an environment such as Python so that a developer could drop privileges, for example, open files for writing and then drop the privilege to open any further files.
The specific syscalls are quite new. Theo de Raadt gave this talk on pledge in 2015, and you can see that it was a bit different then. The "pledge path" feature never had a good enough API that didn't slow down the system too much, so they split that functionality into unveil a few years later. this video
Google patches the snot out of the Linux kernel in Android. In fact in now contains a fair amount of ideas from OpenBSD. Theo De Raadt talks about some of the in his Pledge talk: this video