[ Merge of http://go/wvgerrit/113750 ]
This introduces two classes EccPublicKey and EccPrivateKey which
perform all ECC-specific crypto operations. The main operations
required by ECC are:
- Load/serialize keys from/to X.509 DER formats
- Generate ECC signatures
- Verify ECC signatures
- Derive session keys used by other OEMCrypto operations
These new classes still need to be plugged into rest of the reference
OEMCrypto implementation.
Bug: 135283522
Test: Future CL
Change-Id: Id071cad9129f95a6eb08662322154ba7d1548d40
