sign.go

func (self IEOSigner) IEOSign(contributor ethereum.Address, userid uint64, ieoid *big.Int) (string, string, string, error) {
	// 1. concat all bytes of contributor, userid (0 padded to 32 bytes), ieoid (0 padded to 32 bytes)
	contributorBytes := ethereum.LeftPadBytes(contributor.Big().Bytes(), 20)
	useridBytes := ethereum.LeftPadBytes(big.NewInt(int64(userid)).Bytes(), 32)
	ieoidBytes := ethereum.LeftPadBytes(ieoid.Bytes(), 32)
	concat := append(contributorBytes, useridBytes...)
	concat = append(concat, ieoidBytes...)
	// 2. sha3 the concatenation to get msg
	msg := crypto.Keccak256(concat)
	fmt.Printf("msg: %s\n", ethereum.ToHex(msg))
	// 3. sign the msg to get signed msg
	signed, err := secp256k1.Sign(msg, self.priv)
	if err != nil {
		return "", "", "", err
	}
	// 4. extract r, s, v from signed msg
	r := signed[0:32]
	s := signed[32:64]
	v := signed[64:65]
	return ethereum.ToHex(v), ethereum.ToHex(r), ethereum.ToHex(s), nil
}