On Fri, 2016-08-12 at 05:54 -0700, Andy Lutomirski wrote: > > > Whatever solution we decide, some firmware is already signed. Some of > > the Intel firmware we submit to linux-firmware is signed and a firmware > > with bad or unsigned keys will fail to load on these devices. Now how > > much we are willing to trust that is entirely different question. > > > > Any solution needs to comprehend that additional signing might be > > present. > > I see device-verified signatures as orthogonal: the kernel loads a > blob, optionally verifies the blob, and that blob just happens to > contain a signature. To a certain extent yes. If you *know* the device will check the signature then you might not bother. Then again, this stuff is often fairly opaque and the device *might* not check for itself in some circumstances (prototype hardware, debug modes, etc.) so if there *is* a signature and *if* it isn't just part of an opaque blob, then it might make some sense to validate it for ourselves too. -- dwmw2