11 items tagged “sandboxing”
2024
Cerebras Coder (via) Val Town founder Steve Krouse has been building demos on top of the Cerebras API that runs Llama3.1-70b at 2,000 tokens/second.
Having a capable LLM with that kind of performance turns out to be really interesting. Cerebras Coder is a demo that implements Claude Artifact-style on-demand JavaScript apps, and having it run at that speed means changes you request are visible within less than a second:
Steve's implementation (created with the help of Townie, the Val Town code assistant) demonstrates the simplest possible version of an iframe sandbox:
<iframe
srcDoc={code}
sandbox="allow-scripts allow-modals allow-forms allow-popups allow-same-origin allow-top-navigation allow-downloads allow-presentation allow-pointer-lock"
/>
Where code is populated by a setCode(...) call inside a React component.
The most interesting applications of LLMs continue to be where they operate in a tight loop with a human - this can make those review loops potentially much faster and more productive.
Mastodon discussion about sandboxing SVG data. I asked this on Mastodon and got some really useful replies:
How hard is it to process untrusted SVG data to strip out any potentially harmful tags or attributes (like stuff that might execute JavaScript)?
The winner for me turned out to be the humble <img src=""> tag. SVG images that are rendered in an image have all dynamic functionality - including embedded JavaScript - disabled by default, and that's something that's directly included in the spec:
2.2.6. Secure static mode
This processing mode is intended for circumstances where an SVG document is to be used as a non-animated image that is not allowed to resolve external references, and which is not intended to be used as an interactive document. This mode might be used where image support has traditionally been limited to non-animated raster images (such as JPEG and PNG.)
[...]
'image' references
An SVG embedded within an 'image' element must be processed in secure animated mode if the embedding document supports declarative animation, or in secure static mode otherwise.
The same processing modes are expected to be used for other cases where SVG is used in place of a raster image, such as an HTML 'img' element or in any CSS property that takes an
data type. This is consistent with HTML's requirement that image sources must reference "a non-interactive, optionally animated, image resource that is neither paged nor scripted" [HTML]
This also works for SVG data that's presented in a <img src="data:image/svg+xml;base64,... attribute. I had Claude help spin me up this interactive demo:
Build me an artifact - just HTML, no JavaScript - which demonstrates embedding some SVG files using img src= base64 URIs
I want three SVGs - one of the sun, one of a pelican and one that includes some tricky javascript things which I hope the img src= tag will ignore
If you right click and "open in a new tab" on the JavaScript-embedding SVG that script will execute, showing an alert. You can click the image to see another alert showing location.href and document.cookie which should confirm that the base64 image is not treated as having the same origin as the page itself.
How Anthropic built Artifacts. Gergely Orosz interviews five members of Anthropic about how they built Artifacts on top of Claude with a small team in just three months.
The initial prototype used Streamlit, and the biggest challenge was building a robust sandbox to run the LLM-generated code in:
We use iFrame sandboxes with full-site process isolation. This approach has gotten robust over the years. This protects users' main Claude.ai browsing session from malicious artifacts. We also use strict Content Security Policies (CSPs) to enforce limited and controlled network access.
Artifacts were launched in general availability yesterday - previously you had to turn them on as a preview feature. Alex Albert has a 14 minute demo video up on Twitter showing the different forms of content they can create, including interactive HTML apps, Markdown, HTML, SVG, Mermaid diagrams and React Components.
The first four Val Town runtimes
(via)
Val Town solves one of my favourite technical problems: how to run untrusted code in a safe sandbox. They're on their fourth iteration of this now, currently using a Node.js application that launches Deno sub-processes using the node-deno-vm npm package and runs code in those, taking advantage of the Deno sandboxing mechanism and terminating processes that take too long in order to protect against while(true) style attacks.
2023
In general my approach to running arbitrary untrusted code is 20% sandboxing and 80% making sure that it’s an extremely low value attack target so it’s not worth trying to break in.
Programs are terminated after 1 second of runtime, they run in a container with no network access, and the machine they’re running on has no sensitive data on it and a very small CPU.
Cyber (via) “Cyber is a new language for fast, efficient, and concurrent scripting.” Lots of interesting ideas in here, but the one that really caught my eye is that its designed to be easily embedded into other languages and “will allow the host to insert gas mileage checks in user scripts. This allows the host to control how long a script can run”—my dream feature for implementing a safe, sandboxed extension mechanism! Cyber is implemented using Zig and LLVM.
Python Sandbox in Web Assembly (via) Jim Kring responded to my questions on Mastodon about running Python in a WASM sandbox by building this repo, which demonstrates using wasmer-python to run a build of Python 3.6 compiled to WebAssembly, complete with protected access to a sandbox directory.
2020
Sandboxing and Workload Isolation (via) Fly.io run other people’s code in containers, so workload isolation is a Big Deal for them. This blog post goes deep into the history of isolation and the various different approaches you can take, and fills me with confidence that the team at Fly.io know their stuff. I got to the bottom and found it had been written by Thomas Ptacek, which didn’t surprise me in the slightest.
2010
premasagar’s sandie. “Sandie is a simple method for loading external JavaScript files into a page without affecting the global scope, to avoid collisions between conflicting scripts”—works by loading the script in an invisible iframe (hence a new global scope) and then passing a reference to a callback function in the parent page.
2008
Secure mashups with dojox.secure (via) dojox.secure is brilliant and terrifying at the same time. It provides a full featured API for running untrusted JavaScript in a sandbox, by parsing and validating that code against a variant of Douglas Crockford’s ADsafe JavaScript subset. It could be fantastically useful, but it’s difficult to judge how secure this approach really is.
YUI 3.0 Preview Release 1. YUI sandboxing is a really good idea, which cleverly addresses both the need to run multiple versions of the library at once and the complaints about how verbose traditional YUI code can get.