[OOM-K8S-CERT-EXTERNAL-PROVIDER] Filter not supported CSR properties

Align EJBCA config with OOM

Issue-ID: OOM-2559
Signed-off-by: Remigiusz Janeczek <remigiusz.janeczek@nokia.com>
Change-Id: I8ab73c84415e1ea1b09b6210ffbf84386315f9eb

1 files changed, 62 insertions, 0 deletions

diff --git a/certServiceK8sExternalProvider/src/cmpv2provisioner/csr/csr.go b/certServiceK8sExternalProvider/src/cmpv2provisioner/csr/csr.go
new file mode 100644
index 00000000..1a86866b
--- /dev/null
+++ b/certServiceK8sExternalProvider/src/cmpv2provisioner/csr/csr.go
@@ -0,0 +1,62 @@
+/*
+ * ============LICENSE_START=======================================================
+ * oom-certservice-k8s-external-provider
+ * ================================================================================
+ * Copyright (C) 2020 Nokia. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package csr
+
+import (
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+
+	x509utils "onap.org/oom-certservice/k8s-external-provider/src/x509"
+)
+
+func FilterFieldsFromCSR(csrBytes []byte, privateKeyBytes []byte) ([]byte, error) {
+	csr, err := x509utils.DecodeCSR(csrBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	key, err := x509utils.DecodePrivateKey(privateKeyBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	filteredSubject := filterFieldsFromSubject(csr.Subject)
+
+	filteredCsr, err := x509.CreateCertificateRequest(rand.Reader, &x509.CertificateRequest{
+		Subject:  filteredSubject,
+		DNSNames: csr.DNSNames,
+	}, key)
+	if err != nil {
+		return nil, err
+	}
+
+	csrBytes = pem.EncodeToMemory(&pem.Block{Type: x509utils.PemCsrType, Bytes: filteredCsr})
+	return csrBytes, nil
+}
+
+func filterFieldsFromSubject(subject pkix.Name) pkix.Name {
+	subject.StreetAddress = []string{}
+	subject.SerialNumber = ""
+	subject.PostalCode = []string{}
+	return subject
+}