// Verify verifies that the message's signature matches its origin,
// returning an error when it doesn't.
func (m Message) Verify() error {
if len(m.Signature) == 0 {
return errors.New("empty signature")
}
hashed := sha256.Sum256(m.PayloadBytes)
pubKey := rsa.PublicKey(m.Origin)
return rsa.VerifyPKCS1v15(&pubKey, crypto.SHA256, hashed[:], m.Signature)
}
func (id identity) Fingerprint() fingerprint {
pubKey := rsa.PublicKey(id)
derEncoded, err := x509.MarshalPKIXPublicKey(&pubKey)
if err != nil {
panic(err)
}
return fingerprint(sha256.Sum256(derEncoded))
}