The Polygons Of Another World
> An other choice would be Eric Chahi’s 1991 critically acclaimed” title “Another World”, better known in North America as “Out Of This World” which also happens to be ubiquitous. I would argue it is in fact more interesting to study than DOOM because of its polygon based graphics which are suitable to wild optimizations. In some cases, clever tricks allowed Another World to run on hardware built up to five years prior to the game release.
> This series is a journey through the video-games hardware of the early 90s. From the Amiga 500, Atari ST, IBM PC, Super Nintendo, up to the Sega Genesis. For each machine, I attempted to discover how Another World was implemented. I found an environment made rich by its diversity where the now ubiquitous CPU/GPU did not exist yet. In the process, I discovered the untold stories of seemingly impossible problems heroically solved by lone programmers.
A very deep dive into iOS Exploit chains found in the wild
> Earlier this year Google’s Threat Analysis Group (TAG) discovered a small collection of hacked websites. The hacked sites were being used in indiscriminate watering hole attacks against their visitors, using iPhone 0-day.
> There was no target discrimination; simply visiting the hacked site was enough for the exploit server to attack your device, and if it was successful, install a monitoring implant. We estimate that these sites receive thousands of visitors per week.
> TAG was able to collect five separate, complete and unique iPhone exploit chains, covering almost every version from iOS 10 through to the latest version of iOS 12. This indicated a group making a sustained effort to hack the users of iPhones in certain communities over a period of at least two years.
> I’ll investigate what I assess to be the root causes of the vulnerabilities and discuss some insights we can gain into Apple’s software development lifecycle. The root causes I highlight here are not novel and are often overlooked: we’ll see cases of code which seems to have never worked, code that likely skipped QA or likely had little testing or review before being shipped to users.
Getting Into Browser Exploitation
Last post in series, toc at the top.
> 0x00: New Series: Getting Into Browser Exploitation
> 0x02: The Butterfly of JSObject
> 0x04: WebKit RegExp Exploit addrof() walk-through
> 0x05: The fakeobj() Primitive: Turning an Address Leak into a Memory Corruption
> 0x07: Preparing for Stage 2 of a WebKit exploit
> 0x08: Arbitrary Read and Write in WebKit Exploit
7 Days To Virtualization: A Series On Hypervisor Development
Detecting in C++ whether a type is defined
Pesäpallo: The rules for the casual viewer
Just going to link to the whole blog.
.NET Internals Cookbook
> In this series I answer various .NET questions. Some of them are asked during interviews, some of them I see on the internet, some of them are completely made up. The goal is to provide short answer with links to references if needed. This is by no means a .NET tutorial or experts reference, this is just a bunch of useful answers to refresh your knowledge.
Some of this gets pretty deep actually.
Everything You Need To Know About SVG
> Using SVG can be very simple, but if you start digging in, there is a lot to know about SVG. In this series you’re going to learn why SVG is such an important part of building websites. From why SVG is useful and how to get your hands on it all the way to implementing it as a system and fancy stuff like animating it.
Inside the Apollo Guidance Computer's core memory
> The Apollo Guidance Computer (AGC) provided guidance, navigation and control onboard the Apollo flights to the Moon. This historic computer was one of the first to use integrated circuits, containing just two types of ICs: a 3-input NOR gate for the logic circuitry and a sense amplifier IC for the memory. It also used numerous analog circuits built from discrete components using unusual cordwood construction.
Also core rope: http://www.righto.com/2019/07/software-woven-into-wire-core-rope-and.html
> Erasable core memory and core rope both used magnetic cores, small magnetizable rings. But while erasable core memory used one core for each bit, core rope stored an incredible 192 bits per core, achieving much higher density.2 The trick was to put many wires through each core (as shown above), hardwiring the data: a 1 bit was stored by threading a wire through a core, while the wire bypassed the core for a 0 bit. Thus, once a core rope was carefully manufactured, using a half-mile of wire, data was permanently stored in the core rope.
Also, Bitcoin: http://www.righto.com/2019/07/bitcoin-mining-on-apollo-guidance.html
Also, NOR gates: http://www.righto.com/2019/09/a-computer-built-from-nor-gates-inside.html
> This historic computer was one of the first to use integrated circuits and its CPU was built entirely from NOR gates. In this blog post, I describe the architecture and circuitry of the CPU.
The Intel 80386, part 1: Introduction
> I’ve recently been looking into a fascinating corner of mathematics that at first glance appears a little bit silly, but actually has far-reaching applications, from physics to numerical methods to machine learning. I thought I’d share what I’ve learned over the next few episodes.
> I assume you recall what a complex number is, but perhaps not all of the details. A complex number is usually introduced as a pair of real numbers (a, b), where a is called the “real part” and b is called the “imaginary part”.
> A brief aside: it has always bugged me that these labels are unnecessarily value-laden. There is no particular “reality” that is associated with the real part; it is every bit as “imaginary” as the imaginary part. They might as well be called the “rezrov part” and the “gnusto part”, but we’re stuck with “real” and “imaginary”. Moving on.
Windows Command-Line: Introducing the Windows Pseudo Console (ConPTY)
> In this, the fourth post in the Windows Command-Line series, we’ll discuss the new Windows Pseudo Console (ConPTY) infrastructure and API - why we built it, what it’s for, how it works, how to use it, and more.
Vectorized Emulation: Hardware accelerated taint tracking at 2 trillion instructions per second
> In this blog I’m going to introduce you to a concept I’ve been working on for almost 2 years now. Vectorized emulation. The goal is to take standard applications and JIT them to their AVX-512 equivalent such that we can fuzz 16 VMs at a time per thread. The net result of this work allows for high performance fuzzing (approx 40 billion to 120 billion instructions per second [the 2 trillion clickbait number is theoretical maximum]) depending on the target, while gathering differential coverage on code, register, and memory state.
> Further since we’re running emulated code we are able to run a soft MMU implementation which has byte-level permissions. This gives us stronger-than-ASAN memory protections, making bugs fail faster and cleaner.
Bitslicing, An Introduction
> Bitslicing (in software) is an implementation strategy enabling fast, constant-time implementations of cryptographic algorithms immune to cache and timing-related side channel attacks. This post intends to give a brief overview of the general technique, not requiring much of a cryptographic background. It will demonstrate bitslicing a small S-box, talk about multiplexers, LUTs, Boolean functions, and minimal forms.
The PowerPC 600 series
> As with all the processor retrospective series, I’m going to focus on how Windows NT used the PowerPC in user mode because the original audience for all of these discussions was user-mode developers trying to get up to speed debugging their programs on PowerPC.
Swallowing the elephant
> Years ago while interning in the rendering group at Pixar, I learned an important lesson: “interesting” things almost always come to light when a software system is given input with significantly different characteristics than it’s seen before. Even for well-written and mature software systems, new types of input almost always expose heretofore unknown shortcomings in the existing implementation.
The MIPS R4000
Stop cherry-picking, start merging