This repo contains code which can generate Shamir Secret keys for a specified secret key and also regenerate the secret key with only two of the 4 secret keys generated.
In theory there can be n secret keys generated for a specified secret, but for simplicity we only generate 4 in this example.
PS: Since this is TS, older brother of JS, it's bound to have some mathematical precision errors which I wish to be neglected.
This example takes in the quorum coefficient to be 2, i.e the number of points required to regenerate the keys.
The code lives in src/index.ts file.
generateKeys: This function takes in a number and returns an array of (x, y) coordinate keys for a specified secret. Out of these only 2 are required to reconstruct the secret keys.
getSecret: This function takes in an array of 2 (x, y) coordinates which can be used to reconstruct the original polynomial using lagrange's basis polynomial and hence the secret which was used as the constant.