search

w3c-ccg / did-spec

Please see README.md for latest version being developed by W3C DID WG.
https://w3c.github.io/did-core/
Other
124 stars 45 forks source link

Add support for recoverable public keys #201

Closed awoie closed 5 years ago

awoie commented 5 years ago

Some DID methods like did:ethr [1] use function(publicKey), i.e. EthereumAddress, as the the public verification key (digital signature) in the DID Document instead of the public key itself. A verifier would recover the public key from a signature plus the signed message and then, test if function(publicKeyRecovered) is included in the DID Document.

In the case of did:ethr, it will be a secp256k1 key that signs the message, and the EthereumAddress will be included in the DID Document which is function(publicKey) = 0x + tail(keccak-256(publicKey), 20)

We should add support for another public key type (Secp256k1VerificationKeyRecoverable2018 in addition to Secp256k1VerificationKey2018), and encoding (EthereumAddress in addition to publicKeyPem) that supports this approach. This enables every Ethereum account to be the owner of a DID and saves a lot of transaction fees when the DID is anchored on a public Blockchain like Ethereum, or Bitcoin.

[1] https://github.com/uport-project/ethr-did-resolver/blob/develop/doc/did-method-spec.md

peacekeeper commented 5 years ago

Related to (or duplicate of) https://github.com/w3c-ccg/did-spec/issues/56.

Also see https://github.com/WebOfTrustInfo/rwot6-santabarbara/issues/63.

awoie commented 5 years ago

Yes, I agree. We can close this issue and I will follow up on the other thread.

peacekeeper commented 5 years ago

Note that a new Linked Data Cryptographic Suite https://github.com/w3c-dvcg/lds-ecdsa-secp256k1-2019 has been created, which can define an ethereumAddress public key property.