Dr. Brian Callahan

1.2K Followers
258 Following
4.3K Posts

Prof, ITWS@RPI
Graduate Program Director, ITWS@RPI
Director, Rensselaer Cybersecurity Collaboratory

EN (native)/日本語(N4/N5 レベル)
私は日本語を勉強しています。

CISSP
#OpenBSD developer
NYC*BUG admin
I have been known to write articles for #ARRL #QEX.

#Anthropology #Collaboration #DigitalHumanities
#יהודי
#HamRadio #AmateurRadio #HamR #InformationSecurity #InfoSec #CyberSecurity #CyberSec #professor #academic #academia

PronounsHe/Him
Websitehttps://briancallahan.net
CallsignAD2BA
May the way of the Herolead to the Triforce.
@Lioh Yes, I have come to learn that I am the only one who likes it without padding so it is on my todo list.
@florian I’m not disappearing just changing how I contribute.

New #blog post alert!

I muse about research some of my grad students and I did around independently evaluating some #OpenBSD anti-ROP mitigations, and I bid farewell to being an OpenBSD developer.

https://briancallahan.net/blog/20260322.html

#freebsd #netbsd #dragonflybsd #bsd #unix #linux #compiler #compilers #rop #research

Semi-retirement, or, really, changing my relationship with the BSDs - Dr. Brian Robert Callahan

New #blog post!

I install #FreeBSD 15.-0-RELEASE on a Raspberry Pi Zero 2 W. You can too!

https://briancallahan.net/blog/20251216.html

#openbsd #netbsd #linux #unix #solaris #illumos #arm #arm64 #aarch64

Let's run FreeBSD 15.0-RELEASE on a Raspberry Pi Zero 2 W - Dr. Brian Robert Callahan

Release oksh-7.8 · ibara/oksh

This is oksh-7.8 SHA256 (oksh-7.8.tar.gz) = 3b30d5a1183b829590cc020d8ab87f22d288e98dc3fdf12feb7159536beaa950

GitHub

New #blog post. Let's write a peephole optimizer for #QBE that operates on #AArch64 assembly code. Three years ago, we did this for #AMD64 assembly code. But now that I have Arm machines, we can replicate the effort for another CPU architecture.

https://briancallahan.net/blog/20250901.html

#compiler #compilers #opensource #freesoftware #unix #bsd #freebsd #openbsd #netbsd #dragonflybsd #linux #illumos #macos #assembler #assembly

Let's write a peephole optimizer for QBE's arm64 backend - Dr. Brian Robert Callahan

You ever buy a Blu ray of a TV show on a whim, figure you'll watch one episode, then end up watching the whole thing in one sitting, only to realize that while you did also buy the second season, you won't have it for a week.

This is me right now 

@alanc Noted!
I finally after multiple years of procrastination added dark mode to my website. It currently does auto-detecting based on your system; I'll have to add a little button or something. But it works.

@alanc I mention in the blog post my disbelief that GNAT had no general Solaris support. It really just seemed a case of no one tried gave way to people assumed it didn't work gave way to ossified "knowledge" that was in fact incorrect. And it takes someone to try to break the ossification, which I was happy to do.

(As an aside, I notice Solaris doesn't ship a gdc package. It would be trivial to add it as D already supports Solaris. If it's something I can do let me know and I will try to figure out IPS packaging.)