bls.go

package bls

import (
	"crypto/sha512"
	"encoding/hex"
	"math/big"
	"strings"

	bls12381 "github.com/kilic/bls12-381"
	"golang.org/x/crypto/pbkdf2"
)

func KeyGen(seed []byte) PrivateKey {
	L := 48
	okm := extractExpand(L, append(seed, 0), []byte("BLS-SIG-KEYGEN-SALT-"), []byte{0, byte(L)})

	return PrivateKey{new(big.Int).Mod(new(big.Int).SetBytes(okm), bls12381.NewG1().Q())}
}

func KeyFromBytes(keyBytes []byte) PrivateKey {
	return PrivateKey{
		value: new(big.Int).SetBytes(keyBytes),
	}
}

func KeyFromHexString(key string) (PrivateKey, error) {
	key = strings.TrimPrefix(key, "0x")
	keyBytes, err := hex.DecodeString(key)
	if err != nil {
		return PrivateKey{}, err
	}
	return KeyFromBytes(keyBytes), nil
}

func KeyGenWithMnemonic(mnemonic, password string) PrivateKey {
	seed := newSeed(mnemonic, password)
	return KeyGen(seed)
}

func newSeed(mnemonic, password string) []byte {
	return pbkdf2.Key([]byte(mnemonic), []byte("mnemonic"+password), 2048, 64, sha512.New)
}