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Everything used to be open and relatively well-defined on the platform, unless my memory is colored rosey: BIOS, MBR, HDD, etc. Generally, it still is beginning

Everything used to be open and relatively well-defined on the platform, unless my memory is colored rosey: BIOS, MBR, HDD, etc. Generally, it still is beginning with BIOS (AFAIK, you can usually disable UEFI). But 'pre-BIOS' vendors have created a mostly proprietary, closed hodge-podge of hardware and software. I've been trying to merely identify those components and subsystems on a new computer and it's taking many hours and information is sparse. There's TPM, PTT, ME, TXT, Boot Guard, AMT, etc. etc. All seem to serve one or more of three purposes: 1) Manageability (for corporate IT), 2) end-user control via a Root of Trust (practical only for corporate IT for the most part), and 3) Vendor control (DRM and more) via a root of trust and closed, undocumented, obscure systems. Is there any guide to all this? Any standardization? There were and are multiple BIOS vendors, but generally I knew what a BIOS did and does.

gh02t 9y ago
I dunno, BIOS was pretty opaque and all the major BIOS vendors stuff was completely proprietary (and often full of bugs). The difference is that BIOS was simpler and hence easier to understand. It was also not as well-protected and if you wanted to you could extract and reverse engineer the BIOS with easily available tools. Nowadays the firmware in your machine is better protected as well as much more complex, making it harder to access and harder to understand.
- userbinator 9y ago
  The parent comment is saying "used to be", and that was actually very true before the IBM PS/2 and the AT clones --- IBM published the schematics and BIOS source code for the PC, XT, and AT in the PC Technical Reference books. https://archive.org/details/bitsavers_ibmpcat618ferenceMar86_25829277 https://archive.org/details/bitsavers_ibmpcat618ferenceMar86... Even in the "AT clone" era (better known as "IBM PC Compatible"), the standards were relatively more open and there wasn't much in the way of DRM at all.
- fao_ 9y ago
  > Nowadays the firmware in your machine is better protected https://www.blackhat.com/eu-17/briefings/schedule/#how-to-hack-a-turned-off-computer-or-running-unsigned-code-in-intel-management-engine-8668 https://www.blackhat.com/eu-17/briefings/schedule/#how-to-ha...
kogepathic 9y ago
> Is there any guide to all this? Any standardization? UEFI is standardized. The reference implementation of UEFI called EDK II is even open source. [0] However original device manufacturers (ODMs) are lazy, and independent BIOS vendors (IBVs) have moved in to offer ODMs customization (e.g. the fancy configuration GUI) based on EDK II but which aren't open source and are sprinkled with their proprietary magic. Think AMI, Phoenix, etc. the same people who were making BIOSes. The specific Intel features like TXT, Boot Guard, AMT, etc are not to my knowledge open specifications, so if you wanted more information, you'd probably need to sign a very long NDA with Intel. Clearly there is information available, since the IBVs integrate this functionality into their product. In summary: - UEFI is an open standard with an open source reference implementation [0] - TPM is an open standard. [1] - Intel specific features are, to my knowledge, proprietary - IBV products (AMI, Phoenix) are proprietary [0] https://github.com/tianocore/edk2 https://github.com/tianocore/edk2 [1] https://en.wikipedia.org/wiki/Trusted_Platform_Module https://en.wikipedia.org/wiki/Trusted_Platform_Module

gh02t 9y ago

I dunno, BIOS was pretty opaque and all the major BIOS vendors stuff was completely proprietary (and often full of bugs). The difference is that BIOS was simpler and hence easier to understand. It was also not as well-protected and if you wanted to you could extract and reverse engineer the BIOS with easily available tools. Nowadays the firmware in your machine is better protected as well as much more complex, making it harder to access and harder to understand.

userbinator 9y ago
The parent comment is saying "used to be", and that was actually very true before the IBM PS/2 and the AT clones --- IBM published the schematics and BIOS source code for the PC, XT, and AT in the PC Technical Reference books. https://archive.org/details/bitsavers_ibmpcat618ferenceMar86_25829277 https://archive.org/details/bitsavers_ibmpcat618ferenceMar86... Even in the "AT clone" era (better known as "IBM PC Compatible"), the standards were relatively more open and there wasn't much in the way of DRM at all.
fao_ 9y ago
> Nowadays the firmware in your machine is better protected https://www.blackhat.com/eu-17/briefings/schedule/#how-to-hack-a-turned-off-computer-or-running-unsigned-code-in-intel-management-engine-8668 https://www.blackhat.com/eu-17/briefings/schedule/#how-to-ha...

kogepathic 9y ago

> Is there any guide to all this? Any standardization? UEFI is standardized. The reference implementation of UEFI called EDK II is even open source. [0] However original device manufacturers (ODMs) are lazy, and independent BIOS vendors (IBVs) have moved in to offer ODMs customization (e.g. the fancy configuration GUI) based on EDK II but which aren't open source and are sprinkled with their proprietary magic. Think AMI, Phoenix, etc. the same people who were making BIOSes. The specific Intel features like TXT, Boot Guard, AMT, etc are not to my knowledge open specifications, so if you wanted more information, you'd probably need to sign a very long NDA with Intel. Clearly there is information available, since the IBVs integrate this functionality into their product. In summary: - UEFI is an open standard with an open source reference implementation [0] - TPM is an open standard. [1] - Intel specific features are, to my knowledge, proprietary - IBV products (AMI, Phoenix) are proprietary [0] https://github.com/tianocore/edk2 https://github.com/tianocore/edk2 [1] https://en.wikipedia.org/wiki/Trusted_Platform_Module https://en.wikipedia.org/wiki/Trusted_Platform_Module