# go-blindsecp256k1 [![GoDoc](https://godoc.org/github.com/arnaucube/go-blindsecp256k1?status.svg)](https://godoc.org/github.com/arnaucube/go-blindsecp256k1) [![Go Report Card](https://goreportcard.com/badge/github.com/arnaucube/go-blindsecp256k1)](https://goreportcard.com/report/github.com/arnaucube/go-blindsecp256k1) [![Test](https://github.com/arnaucube/go-blindsecp256k1/workflows/Test/badge.svg)](https://github.com/arnaucube/go-blindsecp256k1/actions?query=workflow%3ATest) Blind signature over [secp256k1](https://en.bitcoin.it/wiki/Secp256k1), based on *"[New Blind Signature Schemes Based on the (Elliptic Curve) Discrete Logarithm Problem](https://sci-hub.do/10.1109/ICCKE.2013.6682844)"* paper by Hamid Mala & Nafiseh Nezhadansari. **WARNING**: this repo is experimental, do not use in production. ## Usage ```go import ( [...] "github.com/arnaucube/go-blindsecp256k1" ) [...] // signer: create new signer key pair sk := blindsecp256k1.NewPrivateKey() signerPubK := sk.Public() // signer: when user requests new R parameter to blind a new msg, // create new signerR (public) with its secret k k, signerR := blindsecp256k1.NewRequestParameters() // user: blinds the msg using signer's R msg := new(big.Int).SetBytes([]byte("test")) msgBlinded, userSecretData, err := blindsecp256k1.Blind(msg, signerR) require.Nil(t, err) // signer: signs the blinded message using its private key & secret k sBlind, err := sk.BlindSign(msgBlinded, k) require.Nil(t, err) // user: unblinds the blinded signature sig := blindsecp256k1.Unblind(sBlind, userSecretData) // signature can be verified with signer PublicKey verified := blindsecp256k1.Verify(msg, sig, signerPubK) assert.True(t, verified) ``` ## WASM usage WASM wrappers for browser usage can be found at the [wasm](https://github.com/arnaucube/go-blindsecp256k1/tree/master/wasm/) directory with an example in html&js.