Problems

1. Constructing a threshold signature scheme requires collaboration between members of the signing group. We want to make this collaboration more transparent, to expose malicious parties.
2. Multi-signature smart contracts are normally directly controlled by on-chain interactions with each signatory. We want to enable trusted inputs to multi-signature smart contracts that can be constructed off-chain and evaluated in O(1) time and space.
3. Resource-constrained devices cannot gain information in a trusted way. We want to show that a BLS threshold signature scheme can be constructed partially on-chain, allowing to sign important information such as block headers.

Solution

Key exchange for a Boneh-Lynn-Shacham threshold signature scheme on a smart contract.

The full story

See the writeup here: https://gitlab.com/empathy/lord-of-the-rings/blob/master/On-chain%20zero-knowledger%20threshold%20signatures.pdf (judges, please use this instead of the document uploaded to devpost, as we can't find a way to edit that one)

Built With

• ethereum
• javascript
• solidity
• truffle