This article explains the paper [Herlihy, 2018]1 in simple words. In the paper, Herlihy has introduced an effective atomic cross-chain swap protocol in order to exchange assets across multiple blockchains among multiple parties.
JoyID is a multichain, cross-platform, passwordless and mnemonic-free wallet solution based on FIDO WebAuthn protocol and Nervos CKB. This post shows how to verify the signature from the method signChallenge of the @joyid/ckb package. The method reference page has a demo. I use the demo to obtain an example response then verify the response using the OpenSSL command line and the Python library PyCryptodome. The JoyID follows the WebAuthn specification and employs secp256r1 for signing. Although the guide references section 6.3.3 of the WebAuthn specification, titled “The authenticatorGetAssertion Operation”, I discovered that the example in this repository provided me much more helps.
I recently worked in a Ruby on Rails project which should integrate with many different payment systems. There system mostly use RSA in encryption and signature. However they provide the RSA keys in different formats, it is a challenge to choose a right way to read the keys in Ruby. RSA is an asymmetric cryptographic algorithm, thus it requires two keys, private key and public key. The key itself is just binary, but it can be encoded in different format.