bartzjegr / ipfs-ext

Validates IPFS resources served by Cloudflare's gateway.

IPFS Gateway Validator

Validates IPFS resources served by Cloudflare's gateway.

This repo contains the source code for a browser extension that intercepts requests to IPFS gateways and distinguished domain names, and cryptographically verifies that the server's response is valid. It currently only works in Firefox because Firefox is the only browser that supports the webRequest.filterResponseData() API.

Currently, it intercepts any request to:

• Cloudflare's gateway, https://cloudflare-ipfs.com
• Any domain starting with "ipfs-sec.". For example, ipfs-sec.stackexchange.cloudflare-ipfs.com.

What are ipfs-sec domains for?

ipfs-sec domains have several security and usability properties that make them ideal for building trust-minimizing web apps.

Unlike requests served by a communal or local gateway, ipfs-sec domains are considered by the browser as a distinct origin. This means they have a safe place to store cookies and local data, can request special permissions from the user, and can run service workers free from manipulation by malicious third-party documents.

Web apps with an ipfs-sec domain can be served by a CDN to reduce their operational cost and load time through caching, as well as provide protection from DDoS attacks. However, unlike with a traditional web app, the website owner is assured that the CDN cannot maliciously modify his content. The user could also be assured that the website owner hasn't maliciously modified their own web app through the use of a Certificate Transparency-like system for DNS, though this is not currently implemented.

Finally, ipfs-sec domains are backwards-compatible. Users that don't want to install the extension will be served the same content as users that do have the extension, they just won't get the security benefits.

You can read more about ipfs-sec, including how to create an ipfs-sec website, in our blog post about end-to-end integrity.

How do I build the extension?

npm run build

Notes

• Only the SHA-256 hashing algorithm is currently supported for content IDs.
• Storing IPFS hashes in TXT records is supported, but the name for the TXT record must be prefixed with "_dnslink".