Change the low-level Quote() functions so that the PCRs to be
included in the quote is selectable. Does not change the
high-level attestPlatform functions, which still retrieve
all PCRs.
The change is a no-op for existing clients, and it will simplify
adding the support for ECC EKs. The activation code no longer makes
assumptions about EK's type and handle (i.e. RSA and 0x81010001),
and instead relies on TPM.EKs() to provide the EK's details.
* AKPublic.Verify: Return an error if a provided PCR of the correct
digest was not included in the quote.
* AKPublic.VerifyAll: Implement VerifyAll method, which can cross-check
that provided PCRs were covered by quotes across PCR banks.
* PCR.QuoteVerified(): Introduce getter method to expose whether a
PCR value was covered during quote verification.
* replace CertifyCreation() by CertifyEx() to handle certification of objects for which we cannot extract CreationData
* add AK.Certify(handle) allowing to certify externally-created keys
* replace ReadPublic() by DecodePublic() when creating and loading keys: the current implementation calls ReadPublic() even if public data is already accessible
* drop handle() from the ak interface: it is unnecessary
* add Blobs() to attest.Key: to allow agnostic key marshaling
It's best practice to define as much code, especially exported API, in
files that can build on any platform. With as little code as possible in
OS specific files.
Ensure files with build tags don't contain any exported APIs. This helps
us not accidentally define API that only works on one platform, or have
incompatible method defintions between OSes.
TODO: follow up with an "unsupported" implementation so this builds on
Mac or without CGO (e.g. for servers)?
Event log parsing requires knowning both the public key and signing
parameters. Symmantically, this information should be from an attested
public key blob, not additional data passed by the client.
Introduce a new method for parsing an AIK's public key blob, returning
a new AIKPublic struct.
We plan to identify AIKs based on their public key. The raw blob should
be available via the AttestationParameters, but we hope that users will
only use that struct for generating challenges.
Because this parses the public key on AIK creation and loading, this PR
should have existing coverage.
* Refactor serialized keys into own structure, in preparation for making Key an interface.
* Refactor key logic into separate structures for each platform/TPMversion invariant.
* Implement review feedback
