if err != nil {
			return nil, nil, nil, err
		}
		ech.kdfID, ech.aeadID = suite.KDFID, suite.AEADID
		info := append([]byte("tls ech\x00"), ech.config.raw...)
		ech.encapsulatedKey, ech.hpkeContext, err = hpke.SetupSender(ech.config.KemID, suite.KDFID, suite.AEADID, echPK, info)
		if err != nil {
			return nil, nil, nil, err
		}
	}

	return hello, keyShareKeys, ech, nil
}

type echContext struct {