BLS 12-381 util

BLS 12-381 util (BLSU, "bless you") is a collection of utils to work with BLS 12-381 in Go.

Warning: these wrapper utils have not been audited.

This package wraps github.com/kilic/bls12-381, a pure Go implementation of BLS, no CGO involved, no special dependencies. Instead, this BLS implementation uses Go-assembly to optimize the lower level computations. audit info.

This package implements the BLS_SIG_BLS12381G2_XMD:SHA-256_SSWU_RO_POP_ ciphersuite.

TODO: not safe for 32 bit usage: kilic BLS Fr.FromBytes->Fr.fromBytes->Fr.fromBig assumes word size is 64 bits.

Utils

• Eth2 Typing
  • Pubkeys: PointG1 wrapper
  • Signatures: PointG2 wrapper
  • Secret keys: Fr wrapper
  • Signatures sets: see below
• Draft 4 for signatures
  • Hash to curve, from kilic/bls12-381: BLS12381G2_XMD:SHA-256_SSWU_RO_
  • Schemes:
    • Core operations:
      • KeyGen (TODO)
      • SkToPk
      • KeyValidate, implemented as part of Pubkey deserialization,
        except identity-pubkey check (checked in verify functions instead).
      • CoreSign
      • CoreVerify
      • Aggregate
      • CoreAggregateVerify
    • Basic scheme, not supported
    • Message Augmentation scheme, not supported
    • POP, Proof of Possession scheme (used in Eth2):
      • PopProve, not supported, assumed through application-specific implementation
      • PopVerify, not supported, assumed through application-specific implementation
      • FastAggregateVerify
• Eth2 additions
  • eth2_aggregate_pubkeys: AggregatePubkeys
  • eth2_fast_aggregate_verify: Eth2FastAggregateVerify
• Signature sets: verify non-singular set of signatures and its respective pubkeys and messages

Testing

• Unit tests
  • SecretKey deserialization/serialization
  • Pubkey deserialization/serialization (with KeyValidate routine, except identity-pubkey check)
  • Signature deserialization/serialization
  • SkToPk (TODO: expand)
  • SignatureSetVerify
• Eth2 BLS tests
  • Sign
  • Aggregate
  • Verify
  • AggregateVerify
  • FastAggregateVerify
  • AggregatePubkeys
  • Eth2FastAggregateVerify
• Eth2 spec tests
  • Integrate into ZRNT, run full eth2 test-suite
• standard tests (if any)
  • TODO, need standard signature-scheme test vectors (Work in progress)
  • Run Hash-to-curve test-vectors on kilic/bls12-381 internals

License

MIT, see LICENSE file.