Add option to start https listener

Added support for tls connection for k8splugin.
It will load the certificates from its current folder.
Any installer needs to just put these files in the same
folder as the executable and it will pick them up and start
in https mode.

Issue-ID: MULTICLOUD-570
Change-Id: I505135daa3933b76023c941e7bee54be65fa791f
Signed-off-by: Kiran Kamineni <kiran.k.kamineni@intel.com>

1 files changed, 107 insertions, 0 deletions

diff --git a/src/k8splugin/internal/auth/auth.go b/src/k8splugin/internal/auth/auth.go
new file mode 100644
index 00000000..3da8f2af
--- /dev/null
+++ b/src/k8splugin/internal/auth/auth.go
@@ -0,0 +1,107 @@
+/*
+ * Copyright 2018 Intel Corporation, Inc
+ *
+ * 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 auth
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/base64"
+	"encoding/pem"
+	"io/ioutil"
+	"log"
+
+	pkgerrors "github.com/pkg/errors"
+)
+
+// GetTLSConfig initializes a tlsConfig using the CA's certificate
+// This config is then used to enable the server for mutual TLS
+func GetTLSConfig(caCertFile string, certFile string, keyFile string) (*tls.Config, error) {
+
+	// Initialize tlsConfig once
+	caCert, err := ioutil.ReadFile(caCertFile)
+
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "Read CA Cert file")
+	}
+
+	caCertPool := x509.NewCertPool()
+	caCertPool.AppendCertsFromPEM(caCert)
+
+	tlsConfig := &tls.Config{
+		// Change to RequireAndVerify once we have mandatory certs
+		ClientAuth: tls.VerifyClientCertIfGiven,
+		ClientCAs:  caCertPool,
+		MinVersion: tls.VersionTLS12,
+	}
+
+	certPEMBlk, err := readPEMBlock(certFile)
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "Read Cert File")
+	}
+
+	keyPEMBlk, err := readPEMBlock(keyFile)
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "Read Key File")
+	}
+
+	tlsConfig.Certificates = make([]tls.Certificate, 1)
+	tlsConfig.Certificates[0], err = tls.X509KeyPair(certPEMBlk, keyPEMBlk)
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "Load x509 cert and key")
+	}
+
+	tlsConfig.BuildNameToCertificate()
+	return tlsConfig, nil
+}
+
+func readPEMBlock(filename string) ([]byte, error) {
+
+	pemData, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, pkgerrors.Wrap(err, "Read PEM File")
+	}
+
+	pemBlock, rest := pem.Decode(pemData)
+	if len(rest) > 0 {
+		log.Println("Pemfile has extra data")
+	}
+
+	if x509.IsEncryptedPEMBlock(pemBlock) {
+		password, err := ioutil.ReadFile(filename + ".pass")
+		if err != nil {
+			return nil, pkgerrors.Wrap(err, "Read Password File")
+		}
+
+		pByte, err := base64.StdEncoding.DecodeString(string(password))
+		if err != nil {
+			return nil, pkgerrors.Wrap(err, "Decode PEM Password")
+		}
+
+		pemData, err = x509.DecryptPEMBlock(pemBlock, pByte)
+		if err != nil {
+			return nil, pkgerrors.Wrap(err, "Decrypt PEM Data")
+		}
+		var newPEMBlock pem.Block
+		newPEMBlock.Type = pemBlock.Type
+		newPEMBlock.Bytes = pemData
+		// Converting back to PEM from DER data you get from
+		// DecryptPEMBlock
+		pemData = pem.EncodeToMemory(&newPEMBlock)
+	}
+
+	return pemData, nil
+}