refact(deps): bump k8s and client-go deps to version v0.20.2 (#294)

Signed-off-by: prateekpandey14 <prateek.pandey@mayadata.io>

vendor/k8s.io/client-go/util/cert/cert.go

@@ -28,7 +28,7 @@ import (
 	"io/ioutil"
 	"math/big"
 	"net"
-	"path"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -96,8 +96,8 @@ func GenerateSelfSignedCertKeyWithFixtures(host string, alternateIPs []net.IP, a
 	maxAge := time.Hour * 24 * 365          // one year self-signed certs
 
 	baseName := fmt.Sprintf("%s_%s_%s", host, strings.Join(ipsToStrings(alternateIPs), "-"), strings.Join(alternateDNS, "-"))
-	certFixturePath := path.Join(fixtureDirectory, baseName+".crt")
-	keyFixturePath := path.Join(fixtureDirectory, baseName+".key")
+	certFixturePath := filepath.Join(fixtureDirectory, baseName+".crt")
+	keyFixturePath := filepath.Join(fixtureDirectory, baseName+".key")
 	if len(fixtureDirectory) > 0 {
 		cert, err := ioutil.ReadFile(certFixturePath)
 		if err == nil {

vendor/k8s.io/client-go/util/cert/io.go

@@ -72,7 +72,22 @@ func WriteCert(certPath string, data []byte) error {
 // NewPool returns an x509.CertPool containing the certificates in the given PEM-encoded file.
 // Returns an error if the file could not be read, a certificate could not be parsed, or if the file does not contain any certificates
 func NewPool(filename string) (*x509.CertPool, error) {
-	certs, err := CertsFromFile(filename)
+	pemBlock, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	pool, err := NewPoolFromBytes(pemBlock)
+	if err != nil {
+		return nil, fmt.Errorf("error creating pool from %s: %s", filename, err)
+	}
+	return pool, nil
+}
+
+// NewPoolFromBytes returns an x509.CertPool containing the certificates in the given PEM-encoded bytes.
+// Returns an error if the file could not be read, a certificate could not be parsed, or if the file does not contain any certificates
+func NewPoolFromBytes(pemBlock []byte) (*x509.CertPool, error) {
+	certs, err := ParseCertsPEM(pemBlock)
 	if err != nil {
 		return nil, err
 	}

vendor/k8s.io/client-go/util/cert/pem.go

@@ -17,6 +17,7 @@ limitations under the License.
 package cert
 
 import (
+	"bytes"
 	"crypto/x509"
 	"encoding/pem"
 	"errors"
@@ -59,3 +60,14 @@ func ParseCertsPEM(pemCerts []byte) ([]*x509.Certificate, error) {
 	}
 	return certs, nil
 }
+
+// EncodeCertificates returns the PEM-encoded byte array that represents by the specified certs.
+func EncodeCertificates(certs ...*x509.Certificate) ([]byte, error) {
+	b := bytes.Buffer{}
+	for _, cert := range certs {
+		if err := pem.Encode(&b, &pem.Block{Type: CertificateBlockType, Bytes: cert.Raw}); err != nil {
+			return []byte{}, err
+		}
+	}
+	return b.Bytes(), nil
+}

vendor/k8s.io/client-go/util/cert/server_inspection.go

@@ -0,0 +1,102 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+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 cert
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"net/url"
+	"strings"
+)
+
+// GetClientCANames gets the CA names for client certs that a server accepts.  This is useful when inspecting the
+// state of particular servers.  apiHost is "host:port"
+func GetClientCANames(apiHost string) ([]string, error) {
+	// when we run this the second time, we know which one we are expecting
+	acceptableCAs := []string{}
+	tlsConfig := &tls.Config{
+		InsecureSkipVerify: true, // this is insecure to always get to the GetClientCertificate
+		GetClientCertificate: func(hello *tls.CertificateRequestInfo) (*tls.Certificate, error) {
+			acceptableCAs = []string{}
+			for _, curr := range hello.AcceptableCAs {
+				acceptableCAs = append(acceptableCAs, string(curr))
+			}
+			return &tls.Certificate{}, nil
+		},
+	}
+
+	conn, err := tls.Dial("tcp", apiHost, tlsConfig)
+	if err != nil {
+		return nil, err
+	}
+	if err := conn.Close(); err != nil {
+		return nil, err
+	}
+
+	return acceptableCAs, nil
+}
+
+// GetClientCANamesForURL is GetClientCANames against a URL string like we use in kubeconfigs
+func GetClientCANamesForURL(kubeConfigURL string) ([]string, error) {
+	apiserverURL, err := url.Parse(kubeConfigURL)
+	if err != nil {
+		return nil, err
+	}
+	return GetClientCANames(apiserverURL.Host)
+}
+
+// GetServingCertificates returns the x509 certs used by a server as certificates and pem encoded bytes.
+// The serverName is optional for specifying a different name to get SNI certificates.  apiHost is "host:port"
+func GetServingCertificates(apiHost, serverName string) ([]*x509.Certificate, [][]byte, error) {
+	tlsConfig := &tls.Config{
+		InsecureSkipVerify: true, // this is insecure so that we always get connected
+	}
+	// if a name is specified for SNI, set it.
+	if len(serverName) > 0 {
+		tlsConfig.ServerName = serverName
+	}
+
+	conn, err := tls.Dial("tcp", apiHost, tlsConfig)
+	if err != nil {
+		return nil, nil, err
+	}
+	if err = conn.Close(); err != nil {
+		return nil, nil, fmt.Errorf("failed to close connection : %v", err)
+	}
+
+	peerCerts := conn.ConnectionState().PeerCertificates
+	peerCertBytes := [][]byte{}
+	for _, a := range peerCerts {
+		actualCert, err := EncodeCertificates(a)
+		if err != nil {
+			return nil, nil, err
+		}
+		peerCertBytes = append(peerCertBytes, []byte(strings.TrimSpace(string(actualCert))))
+	}
+
+	return peerCerts, peerCertBytes, err
+}
+
+// GetServingCertificatesForURL is GetServingCertificates against a URL string like we use in kubeconfigs
+func GetServingCertificatesForURL(kubeConfigURL, serverName string) ([]*x509.Certificate, [][]byte, error) {
+	apiserverURL, err := url.Parse(kubeConfigURL)
+	if err != nil {
+		return nil, nil, err
+	}
+	return GetServingCertificates(apiserverURL.Host, serverName)
+}