2 ms·

> You absolutely have to trust whoever manufactured the tpm module not to have back doors. Why? What would a backdoor in the TPM do?

LinuxBender 5y ago
That would depend on future implementations. For example, should Microsoft one day decide to tie session authentication caching to TPM, then a backdoor in the TPM adds a universal chain for a state actor to log into the OS. Worried about state actors? No, but they hire contractors that I probably don't trust to keep this stuff secure. The OS could of course already have a back door, but reversing their code and finding it is higher risk than a closed access chip. I could envision a mandate to relocate the lawful intercept code from the OS to the hardware. Another implementation could be used to tie DRM to hardware and then brick any hardware that is in license violation. Actually I can think of many scenarios that have a unique identifier on the hardware could be used/abused by corporations. It should be noted that I lived through a time when corporations wanted this same setup on televisions. Each TV would have a unique chip that would give corporations control over what a person could watch, or even brick their TV. This was called the V-Chip. [0] And then of course, there was also the Clipper-Chip [1]. In terms of boiling frogs [2], TPM could be the base framework to slowly reintroduce the Clipper-Chip under a different name. i.e. used to boot-strap the pieces of code required to watch movies, buy things, browse the web, anything you can imagine. [0] - https://www.popularmechanics.com/culture/tv/a19408909/20-years-ago-v-chip/ https://www.popularmechanics.com/culture/tv/a19408909/20-yea... [1] - https://en.wikipedia.org/wiki/Clipper_chip https://en.wikipedia.org/wiki/Clipper_chip [2] - https://en.wikipedia.org/wiki/Boiling_frog https://en.wikipedia.org/wiki/Boiling_frog

LinuxBender 5y ago

That would depend on future implementations. For example, should Microsoft one day decide to tie session authentication caching to TPM, then a backdoor in the TPM adds a universal chain for a state actor to log into the OS. Worried about state actors? No, but they hire contractors that I probably don't trust to keep this stuff secure. The OS could of course already have a back door, but reversing their code and finding it is higher risk than a closed access chip. I could envision a mandate to relocate the lawful intercept code from the OS to the hardware. Another implementation could be used to tie DRM to hardware and then brick any hardware that is in license violation. Actually I can think of many scenarios that have a unique identifier on the hardware could be used/abused by corporations. It should be noted that I lived through a time when corporations wanted this same setup on televisions. Each TV would have a unique chip that would give corporations control over what a person could watch, or even brick their TV. This was called the V-Chip. [0] And then of course, there was also the Clipper-Chip [1]. In terms of boiling frogs [2], TPM could be the base framework to slowly reintroduce the Clipper-Chip under a different name. i.e. used to boot-strap the pieces of code required to watch movies, buy things, browse the web, anything you can imagine. [0] - https://www.popularmechanics.com/culture/tv/a19408909/20-years-ago-v-chip/ https://www.popularmechanics.com/culture/tv/a19408909/20-yea... [1] - https://en.wikipedia.org/wiki/Clipper_chip https://en.wikipedia.org/wiki/Clipper_chip [2] - https://en.wikipedia.org/wiki/Boiling_frog https://en.wikipedia.org/wiki/Boiling_frog