Add tls util

internal/util/tls.go

@@ -0,0 +1,64 @@
+// Copyright 2019 Sorint.lab
+//
+// 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.
+
+package util
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"io/ioutil"
+)
+
+func NewTLSConfig(certFile, keyFile, caFile string, insecureSkipVerify bool) (*tls.Config, error) {
+	tlsConfig := tls.Config{}
+
+	// Populate root CA certs
+	if caFile != "" {
+		pemBytes, err := ioutil.ReadFile(caFile)
+		if err != nil {
+			return nil, err
+		}
+		roots := x509.NewCertPool()
+
+		for {
+			var block *pem.Block
+			block, pemBytes = pem.Decode(pemBytes)
+			if block == nil {
+				break
+			}
+			cert, err := x509.ParseCertificate(block.Bytes)
+			if err != nil {
+				return nil, err
+			}
+			roots.AddCert(cert)
+		}
+
+		tlsConfig.RootCAs = roots
+	}
+
+	// Populate keypair
+	// both must be defined
+	if certFile != "" && keyFile != "" {
+		cert, err := tls.LoadX509KeyPair(certFile, keyFile)
+		if err != nil {
+			return nil, err
+		}
+		tlsConfig.Certificates = []tls.Certificate{cert}
+	}
+
+	tlsConfig.InsecureSkipVerify = insecureSkipVerify
+
+	return &tlsConfig, nil
+}