certificate_t->issued_by takes an argument to receive signature scheme

src/libstrongswan/plugins/x509/x509_cert.c

@@ -1483,7 +1483,8 @@ end:
 		/* check if the certificate is self-signed */
 		if (this->public.interface.interface.issued_by(
 											&this->public.interface.interface,
-											&this->public.interface.interface))
+											&this->public.interface.interface,
+											NULL))
 		{
 			this->flags |= X509_SELF_SIGNED;
 		}
@@ -1568,7 +1569,8 @@ METHOD(certificate_t, has_issuer, id_match_t,
 }
 
 METHOD(certificate_t, issued_by, bool,
-	private_x509_cert_t *this, certificate_t *issuer)
+	private_x509_cert_t *this, certificate_t *issuer,
+	signature_scheme_t *schemep)
 {
 	public_key_t *key;
 	signature_scheme_t scheme;
@@ -1612,6 +1614,10 @@ METHOD(certificate_t, issued_by, bool,
 	}
 	valid = key->verify(key, scheme, this->tbsCertificate, this->signature);
 	key->destroy(key);
+	if (valid && schemep)
+	{
+		*schemep = scheme;
+	}
 	return valid;
 }