It concerns me as well as the user-land OS isn't really where control of the RF happens. The OS running in their baseband chip is where the backdoors would best be placed from their perspective. But I'm happy that there are some additional options to run Graphene on the market.
The OS absolutely controls functionality of the baseband, it would be a legal nightmare if it just didn't actually respect proper radio settings. But from a design perspective, it doesn't actually matter that much at all I feel. Any practical and secure design for a cellular phone has to assume the network is totally compromised and hostile, and so it can never be in the trusted base. From this perspective, adding the radio chip and its software to that category is not actually a huge leap. Even today vendors who own all the IP on a bus will still insert IOMMUs, etc inbetween components. It isn't dissimilar to game consoles; they assume that anything outside their die is compromised and hostile, and if you start from that premise, you can still make it very secure even when your threat model includes hostile components on the PCB.
Radio firmware is probably somewhat broken in practice (what isn't these days) but ultimately the openness stuff is a red herring IMO as far as security is concerned, you either assume it's compromised or not.
The userspace OS needs to be where control of any radio (bluetooth, wi-fi, cellular, nfc, uwb etc.) components happens, otherwise it would be difficult to be compliant in terms of regulatory requirements like a working Flight Mode.
Baseband firmware/processors are still making strides in terms of defending against attacks so I don't think we are at the point where backdoors are needed. More likely that undocumented AT commands, plausibly deniable bugdoors and existing memory corruption vulnerabilities are already convenient reality. However, part of that reality is also that once the cellular modem is exploited OTA it is still a massive task to traverse IOMMU restrictions and get device owner data/secrets from the userspace OS. It doesn't even grant visibility into application traffic which has been aggressively TLS encrypted since the mid 2010s.
> The userspace OS needs to be where control of any radio (bluetooth, wi-fi, cellular, nfc, uwb etc.) components happens, otherwise it would be difficult to be compliant in terms of regulatory requirements like a working Flight Mode.
The entities that are putting in backdoors don't respect the law, and obviously will do what they can to obfuscate the backdoor enough to pass regulatory reviews.
My threat model is precisely entities that don't respect law or are unethical. So, the question then boils down to whether current regulatory review processes can catch such backdoors and the people running these processes cannot be bribed or otherwise forced to skip proper review?
It's my understanding that you cannot really defend against backdoors. You can somewhat mitigate their impact through good security/privacy design. Your energies may be better invested in a position that assumes any and all of the radios have been compromised or exploited and work from there (this is what mainstream flagship smartphone SoC/OS designers already do).
In modern phones, doesn't the main chip control the baseband chip rather than the other way? What is the threat model?
Obviously since phone calls and text messages are unencrypted the baseband chip could send them elsewhere. But your internet communication should already be encrypted before it hits the baseband chip. So is the threat model Motorola has intentionally introduced a backdoor to leak data from the main chip to the baseband chip?
"control" is mostly a gentlemans agreement. It sends commands. The OS running in the baseband can decide how to handle the commands. Assuming a malicious vendor, motivated by its host nation, that would be where they could place the most effective backdoors.
Vendors with nefarious intentions or operating on directives from a state agency are a real and valid concern, but the handset under consideration makes use of a Qualcomm baseband chipset, so the OS it runs on is supplied by Qualcomm, not the manufacturer.
If I understand it correctly (but please do correct me if I am wrong), Qualcomm supplies the baseband OS as a signed binary blob.
My knowledge is third-hand as I haven't worked at Motorola for over 20 years (and back then I worked on "server" side, not device side), but I think you are correct. What I'm unclear on is how it differs from the chips (and associated blobs) sold for use in China, where the legal requirements differ, and how reliable the "signing" really is. I do know that some groups get special permission from Qualcomm to load other firmware and expose certain features to the user-land OS. My threat analysis is mostly theoretical and I can't really say that Qualcomms control is lacking or co-opted.
One example, I ran a small batch (20) of 2-layer test/dev boards with some pricier chips on them for something like $2k. It would have cost be like $800 on PCBway. But I've run into enough counterfiet chip issues with PCBWay and such that ate up so much debugging time that the extra cost for Macrofab was fine.
Not familiar with the issue, but that has to be $1m minimum order, correct? And you would get a production run in 1-10k. How many revs does that include?
My understanding is that Shenzhen dominance so far is from 3 pillars - low minimum order size, low per-part price, and fast response. They can do that because they have lot of highly trained labor that work mad hours. So to compete you would need to leverage a lot of automation... which would be a lot less flexible and very rocky at the start. Would love to get a correction from someone more familiar with the situation.
Also Motorola, which is the big incumbent provider for LE systems (911, traffic cams, et al). Axon and Motorola re LOVING Flock taking all the ... flak.
You understand that there is difference between US law enforcement and the intelligence community? And that all service providers are required, by law in almost ALL countries, to respond to legal requests from their governments? What you are citing is not any serious evidence of some shadowy conspiracy between apple and the "government".. Not that I believe Apple's bullshit about protecting users privacy, but you're grasping at straws there.
Thanks, very interesting. Basically the authors blast high-power (~92 dBA) ultrasound around 25kHz and hope that microphone non-linearities will overwhelm the audible signal.
This will sure make all the dogs in 20m radius mad. Hence the solution for the stealth recorder -- bring a dog, then complain about the ultrasound jammer (or at least to be aware of a jammer)
From the paper, it looks like the authors did not consider safety of animals, only human hearing safety.
As someone frequently annoyed by those stupid bird/deer/insect ultrasound emitters I hope this doesn't become common, with my luck I'll be able to hear them.
My neighborhood is full of these anti-social devices which are entirely designed to try to prevent dogs from shitting on their lawns. The noise they make is always at a pitch I can hear and my dog always ignores them.
My dog has no problem shitting on their lawns, and even sometimes pees on the devices.
So I'd like to find any actual devices which work on dogs (well I have no use for it but just to be sure they actually exist), because circa the original iphone I remember that there were apps which could reliably make its microphones do it (and impact dogs as expected).
Which country are you in? Here in GB it is expected that dogs will be under control, and in any case their owners are responsible for any damage they do. Cats on the other hand ... people have devices to scare away cats, though I'm not sure how well they work. Interestingly, cat owners have them in some cases ... to keep their own cat away from certain areas?
yeah I've seen birds nesting on the device itself in places. Other animals acclimate to them, they might work if the animal has basically no reason to want to go there, if they want to they will.
The Home Depot here uses one in the garden area and I can't shop there for more than a couple minutes. our wal-mart used to have one in the produce section, fortunately finally removed.
I'm super excited to try your service and the KiCad plug-in to move supply-chain dialogue closer to point-of-creation makes a TON of sense. That and the speed seem to be the two points of differentiation from Macrofab, who is my current supplier. They will be stiff competition for you as they are a great shop and have a good software interface and a lot of capabilities. I imagine using you guys for quick turn-around needs and them for production and scale?
That is actually what my company built. The primary purpose was for encrypted messaging, but it also acted as secrets store and password manager. The great thing about it being built into the keyboard is there is no chance for a rooted host to intercept passwords/messages etc.
The wonderful thing about our current culture is that each side thinks that further empowering the federal government is the solution. And it will only be used by their side against their enemies (other american citizens). No thought at all to the fact that the other side will take power in 4 years. No, no.. short term power is all that matters. The Biden administration started targeting "right-wing terrorists", now its Trumps turn to take it up a notch. Can't wait to see what the left does when they take power in a couple years. I think the technical term for this is death spiral...
The first few examples aren't every sympathetic (SBF, some pedo, and George Santos), and their argument doesn't appear to be reinforced by the evidence. Though the source is quite long so perhaps they decided to bury the lede.
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