Andrew ZonenbergSecurity and open source at the hardware/software interface. Embedded sec @ IOActive. Lead dev of ngscopeclient/libscopehal. GHz probe designer. Open source networking hardware. "So others may live"
Toots searchable on tootfinder.
Andrew ZonenbergHey @wren6991@types.pl did you guys ever poke at pcie drive strength / emphasis config on the pi4 soc to usb link?
Last time I dropped probes down on the pcie the TX equalizers were waaaay excessive, like set for a PC motherboard sized route. I think I had to remove like 6 dB of emphasis in DSP before the eye looked sane.
Andrew ZonenbergAnybody else think "HBCU" sounds more like a bank than a place to get an education?
Andrew ZonenbergAnybody here gonna be at WOOT '25 in Seattle next week?
I'll be presenting my team's paper "Extraction of Secrets from 40nm CMOS Gate Dielectric Breakdown Antifuses by FIB Passive Voltage Contrast" there.
A sneak peek of this was presented at the HARRIS workshop in Germany earlier this year but HARRIS doesn't publish proceedings or full papers, this is the full peer-reviewed conference paper based on the same work.
https://www.usenix.org/conference/woot25/presentation/zonenberg
I also contributed some material to a broader summary/overview paper describing the entire RP2350 hacking challenge, "Security through Transparency: Tales from the RP2350 Hacking Challenge", also being presented at WOOT
https://www.usenix.org/conference/woot25/presentation/muench
I mostly publish research in informal/industry venues (blogs, industry conferences that don't publish proceedings, etc). These are only going to be my 3rd and 4th formal academic publications.
Andrew ZonenbergIs it possible to make OpenVPN validate that a certificate follows a specific chain?
Use case:
* Internal company root
* Internal company VPN intermediate
* Device certs for each client/server
Is it possible to do something like this but not allow other certs signed by the same root, under a different intermediate, to authenticate to the VPN?