Pass the certifer instance through the cert chain

cert.go

@@ -54,6 +54,7 @@ func (x *certifier) NewCA() (*Cert, error) {
 	}
 
 	return &Cert{
+		x:        x,
 		Template: ca,
 		Bytes:    caBytes,
 		Key:      NewKeyParameters(pk),
@@ -93,6 +94,7 @@ func (c *Cert) NewCert(cn string) (*Cert, error) {
 		ca = c
 	}
 	return &Cert{
+		x:        c.x,
 		Template: cert,
 		Bytes:    certBytes,
 		Key:      NewKeyParameters(pk),
@@ -143,6 +145,7 @@ func (c *Cert) WithoutParentKeys() *Cert {
 		ca.WithoutKeys()
 	}
 	return &Cert{
+		x:        c.x,
 		Template: c.Template,
 		Bytes:    c.Bytes,
 		Key:      c.Key,

certifier.go

@@ -52,6 +52,7 @@ func (x *certifier) Import(data []byte) (*Cert, error) {
 	if err := tGob.Decode(cert); err != nil {
 		return nil, err
 	}
+	cert.x = x
 	return cert, nil
 }