This post will help to provide historical context and demystify what's under the hood of Heads, PureBoot, and other tools to provide Trusted Boot.
I will not be presenting anything new in this article; I merely hope to provide a historical timeline and a curated list of resources.
Intro
The Librem Key cryptographically verifies the system's integrity and flashes red if it's detected tampering
I've always felt bad about two things:
Because I run QubesOS, I usually disable "Secure Boot" on my laptop I travel a lot, and I don't have a good way to verify the integrity of my laptop (eg from an Evil Maid that gains physical access to my computer)
To address this, I have turned to Heads and PureBoot -- a collection of technologies including an open-source firmware/BIOS, TPM, and a USB security key that can cryptographically verify the integrity of the lowest firmware (and up the chain to the OS).
While Purism has written many articles about PureBoot and has some (minimal) documentation, I found they did a lot of hand waving without explaining how the technology works (what the hell is a "BIOS measurement"?). So I spent a great deal of . . . → Read More: Trusted Boot (Anti-Evil-Maid, Heads, and PureBoot)
About six months ago, I discovered something on my smartphone that horrified me: I went to undelete a file in DiskDigger, and I stumbled upon a plethora of unexpected jpegs: screenshots of my activity. Screenshots that I didn't take. Screenshots of my conversations. Screenshots of my GPS position. And screenshots of my bitcoin wallet.
I was perplexed. I was astonished. And, to be honest, I was scared. How did this happen? Was it a vulnerability shipped with LineageOS? Could it be some malicious binary embedded into AOSP? Or is it some exploit in one of those damned closed-source apps that I was forced to install through social pressure (*cough* whatsapp)?
Michael Altfield
Hi, I’m Michael Altfield. I write articles about opsec, privacy, and devops ➡
This article will introduce a tool to detect censorship or network tampering using the Open Observatory of Network Interference (OONI) android app, which is part of the Tor Project.
The OONI project's mission is to collect data on network providers to determine where the Internet is free and where it's being manipulated. For example, the OONI Explorer displays a world map of such data.
On the OONI explorer, you can drill-down on the world map into a specific country to get a list of websites that were detected as being blocked from within that country.
For example, when I looked at the history of OONI probe runs within the US, I saw a list of the usual suspects: gambling sites, pornography sites, torrenting sites, etc. More surprising (at least to me) was the number of pastebin sites that were banned. And, despicably, there was a network in the US blocking The Internet Archive
When I looked at the data from scans within another great "free country" = India, I saw a lot of cherry-picked censorship on facebook and news articles as it relates to the 2017 genocide of Rohingya Refugees in Burma and various muslim/hindu conflicts.
