Who carriers around a phone that doesn't have any activity for months/years?
An activity-generator might help address that.
An activity-generator might help address that.
Firing off as part of a duress key entry, and removing itself (from the decoy partition) as its work is done, would suffice.
ADB / forensic tools would be ineffective if USB access is denied (as discussed elsewhere in this thread).
Well no, because if you gave the pin, you'd expect the phone to work normally, including enabling adb. If you gave the pin but adb doesn't work that would be massively suspicious. Same if adb worked but logs were scrubbed. Otherwise you're back at "border guards found out you gave a duress pin, now you're being prosecuted for tampering with evidence".
It's not clear that all of those objections are substantive or insurmountable.
"The USB port may have died" might be one possible response. (Not technically a lie, and hence defensible in court.) Or just silence.
Alternatively, some way of directing such probes to the decoy partition and presenting a sufficiently coherent impression of a valid partition might be another approach.
Much of this comes down to risks presented and costs of mitigation (or of getting mitigations wrong).
That's about as convincing as "wow this phone just decided to experience catastrophic hardware failure after entering your totally-not-duress pin". Not to mention there's wireless adb.
>Alternatively, some way of directing such probes to the decoy partition and presenting a sufficiently coherent impression of a valid partition might be another approach.
That won't work because they'd notice the adb logs don't correspond to actions taken on the actual phone.
>Much of this comes down to risks presented and costs of mitigation (or of getting mitigations wrong).
Right, which is why grapheneos didn't bother implementing it, because it's a huge effort and it's not worth giving users a false sense of security (eg. thinking that the decoy works when it doesn't), and them getting sent to prison for it.
And why would wireless ADB be enabled? Disable it.
And why would any of this get you sent to prison? If my phone not having wireless ADB or a working USB port, or some set of partitions has become a thing I can go to prison for, then this is totalitarianism and we have already lost by existing?
Once again, you don't seem very interested in opposing this kind of tyranny?
Otherwise that activity would be suspicious due to either a lack of recent records, or of presumably implausible future ones.
Generating data in advance and applying or updating timestamps later, on an ongoing basis, or when a duress code is entered is a possible way of mitigating this. There's the question of how convincing such data would have to be. White-flagging and generating (or appropriating from public sources, e.g., business or institutional entities) contacts for this might be a part of it. This is similar to but not entirely the same as data fuzzing, which is generally seen as applying to a primary data trail.