Merge pull request #1037 from antechrestos/feature/add_option_to_import_registry_certificate

Allow user to provide registry certificate

cmd/executor/cmd/root.go

@@ -154,6 +154,8 @@ func addKanikoOptionsFlags() {
 	RootCmd.PersistentFlags().DurationVarP(&opts.CacheTTL, "cache-ttl", "", time.Hour*336, "Cache timeout in hours. Defaults to two weeks.")
 	RootCmd.PersistentFlags().VarP(&opts.InsecureRegistries, "insecure-registry", "", "Insecure registry using plain HTTP to push and pull. Set it repeatedly for multiple registries.")
 	RootCmd.PersistentFlags().VarP(&opts.SkipTLSVerifyRegistries, "skip-tls-verify-registry", "", "Insecure registry ignoring TLS verify to push and pull. Set it repeatedly for multiple registries.")
+	opts.RegistriesCertificates = make(map[string]string)
+	RootCmd.PersistentFlags().VarP(&opts.RegistriesCertificates, "registry-certificate", "", "Use the provided certificate for TLS communication with the given registry. Expected format is 'my.registry.url=/path/to/the/server/certificate'.")
 	RootCmd.PersistentFlags().StringVarP(&opts.RegistryMirror, "registry-mirror", "", "", "Registry mirror to use has pull-through cache instead of docker.io.")
 	RootCmd.PersistentFlags().BoolVarP(&opts.WhitelistVarRun, "whitelist-var-run", "", true, "Ignore /var/run directory when taking image snapshot. Set it to false to preserve /var/run/ in destination image. (Default true).")
 }

deploy/Dockerfile

@@ -14,7 +14,7 @@
 
 # Builds the static Go image to execute in a Kubernetes job
 
-FROM golang:1.12
+FROM golang:1.13
 ARG GOARCH=amd64
 WORKDIR /go/src/github.com/GoogleContainerTools/kaniko
 # Get GCR credential helper

deploy/Dockerfile_debug

@@ -15,7 +15,7 @@
 # Builds the static Go image to execute in a Kubernetes job
 
 # Stage 0: Build the executor binary and get credential helpers
-FROM golang:1.12
+FROM golang:1.13
 ARG GOARCH=amd64
 WORKDIR /go/src/github.com/GoogleContainerTools/kaniko
 # Get GCR credential helper

deploy/Dockerfile_warmer

@@ -14,7 +14,7 @@
 
 # Builds the static Go image to execute in a Kubernetes job
 
-FROM golang:1.12
+FROM golang:1.13
 ARG GOARCH=amd64
 WORKDIR /go/src/github.com/GoogleContainerTools/kaniko
 # Get GCR credential helper

pkg/config/args.go

@@ -17,6 +17,7 @@ limitations under the License.
 package config
 
 import (
+	"fmt"
 	"strings"
 
 	"github.com/sirupsen/logrus"
@@ -39,6 +40,7 @@ func (b *multiArg) Set(value string) error {
 	return nil
 }
 
+// The third is Type() string
 func (b *multiArg) Type() string {
 	return "multi-arg type"
 }
@@ -51,3 +53,32 @@ func (b *multiArg) Contains(v string) bool {
 	}
 	return false
 }
+
+// This type is used to supported passing in multiple key=value flags
+type keyValueArg map[string]string
+
+// Now, for our new type, implement the two methods of
+// the flag.Value interface...
+// The first method is String() string
+func (a *keyValueArg) String() string {
+	var result []string
+	for key := range *a {
+		result = append(result, fmt.Sprintf("%s=%s", key, (*a)[key]))
+	}
+	return strings.Join(result, ",")
+}
+
+// The second method is Set(value string) error
+func (a *keyValueArg) Set(value string) error {
+	valueSplit := strings.SplitN(value, "=", 2)
+	if len(valueSplit) < 2 {
+		return fmt.Errorf("invalid argument value. expect key=value, got %s", value)
+	}
+	(*a)[valueSplit[0]] = valueSplit[1]
+	return nil
+}
+
+// The third is Type() string
+func (a *keyValueArg) Type() string {
+	return "key-value-arg type"
+}

pkg/config/args_test.go

@@ -0,0 +1,47 @@
+/*
+Copyright 2020 Google LLC
+
+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 config
+
+import "testing"
+
+func TestMultiArg_Set_shouldAppendValue(t *testing.T) {
+	var arg multiArg
+	arg.Set("value1")
+	if len(arg) != 1 || arg[0] != "value1" {
+		t.Error("Fist value was not appended")
+	}
+	arg.Set("value2")
+	if len(arg) != 2 || arg[1] != "value2" {
+		t.Error("Second value was not appended")
+	}
+}
+
+func Test_KeyValueArg_Set_shouldSplitArgument(t *testing.T) {
+	arg := make(keyValueArg)
+	arg.Set("key=value")
+	if arg["key"] != "value" {
+		t.Error("Invalid split. key=value should be split to key=>value")
+	}
+}
+
+func Test_KeyValueArg_Set_shouldAcceptEqualAsValue(t *testing.T) {
+	arg := make(keyValueArg)
+	arg.Set("key=value=something")
+	if arg["key"] != "value=something" {
+		t.Error("Invalid split. key=value=something should be split to key=>value=something")
+	}
+}

pkg/config/options.go

@@ -44,6 +44,7 @@ type KanikoOptions struct {
 	BuildArgs               multiArg
 	InsecureRegistries      multiArg
 	SkipTLSVerifyRegistries multiArg
+	RegistriesCertificates  keyValueArg
 	Insecure                bool
 	SkipTLSVerify           bool
 	InsecurePull            bool

pkg/executor/push.go

@@ -18,6 +18,7 @@ package executor
 
 import (
 	"crypto/tls"
+	"crypto/x509"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -62,6 +63,41 @@ func (w *withUserAgent) RoundTrip(r *http.Request) (*http.Response, error) {
 	return w.t.RoundTrip(r)
 }
 
+type CertPool interface {
+	value() *x509.CertPool
+	append(path string) error
+}
+
+type X509CertPool struct {
+	inner x509.CertPool
+}
+
+func (p *X509CertPool) value() *x509.CertPool {
+	return &p.inner
+}
+
+func (p *X509CertPool) append(path string) error {
+	pem, err := ioutil.ReadFile(path)
+	if err != nil {
+		return err
+	}
+	p.inner.AppendCertsFromPEM(pem)
+	return nil
+}
+
+type systemCertLoader func() CertPool
+
+var defaultX509Handler systemCertLoader = func() CertPool {
+	systemCertPool, err := x509.SystemCertPool()
+	if err != nil {
+		logrus.Warn("Failed to load system cert pool. Loading empty one instead.")
+		systemCertPool = x509.NewCertPool()
+	}
+	return &X509CertPool{
+		inner: *systemCertPool,
+	}
+}
+
 // CheckPushPermissions checks that the configured credentials can be used to
 // push to every specified destination.
 func CheckPushPermissions(opts *config.KanikoOptions) error {
@@ -87,7 +123,7 @@ func CheckPushPermissions(opts *config.KanikoOptions) error {
 			}
 			destRef.Repository.Registry = newReg
 		}
-		tr := makeTransport(opts, registryName)
+		tr := makeTransport(opts, registryName, defaultX509Handler)
 		if err := remote.CheckPushPermission(destRef, creds.GetKeychain(), tr); err != nil {
 			return errors.Wrapf(err, "checking push permission for %q", destRef)
 		}
@@ -184,7 +220,7 @@ func DoPush(image v1.Image, opts *config.KanikoOptions) error {
 			return errors.Wrap(err, "resolving pushAuth")
 		}
 
-		tr := makeTransport(opts, registryName)
+		tr := makeTransport(opts, registryName, defaultX509Handler)
 		rt := &withUserAgent{t: tr}
 
 		if err := remote.Write(destRef, image, remote.WithAuth(pushAuth), remote.WithTransport(rt)); err != nil {
@@ -228,13 +264,22 @@ func writeImageOutputs(image v1.Image, destRefs []name.Tag) error {
 	return nil
 }
 
-func makeTransport(opts *config.KanikoOptions, registryName string) http.RoundTripper {
+func makeTransport(opts *config.KanikoOptions, registryName string, loader systemCertLoader) http.RoundTripper {
 	// Create a transport to set our user-agent.
-	tr := http.DefaultTransport
+	var tr http.RoundTripper = http.DefaultTransport.(*http.Transport).Clone()
 	if opts.SkipTLSVerify || opts.SkipTLSVerifyRegistries.Contains(registryName) {
 		tr.(*http.Transport).TLSClientConfig = &tls.Config{
 			InsecureSkipVerify: true,
 		}
+	} else if certificatePath := opts.RegistriesCertificates[registryName]; certificatePath != "" {
+		systemCertPool := loader()
+		if err := systemCertPool.append(certificatePath); err != nil {
+			logrus.WithError(err).Warnf("Failed to load certificate %s for %s\n", certificatePath, registryName)
+		} else {
+			tr.(*http.Transport).TLSClientConfig = &tls.Config{
+				RootCAs: systemCertPool.value(),
+			}
+		}
 	}
 	return tr
 }

pkg/executor/push_test.go

@@ -18,6 +18,8 @@ package executor
 
 import (
 	"bytes"
+	"crypto/tls"
+	"crypto/x509"
 	"fmt"
 	"io/ioutil"
 	"net/http"
@@ -223,3 +225,85 @@ func TestImageNameDigestFile(t *testing.T) {
 	testutil.CheckErrorAndDeepEqual(t, false, err, want, got)
 
 }
+
+type mockedCertPool struct {
+	certificatesPath []string
+}
+
+func (m *mockedCertPool) value() *x509.CertPool {
+	return &x509.CertPool{}
+}
+
+func (m *mockedCertPool) append(path string) error {
+	m.certificatesPath = append(m.certificatesPath, path)
+	return nil
+}
+
+func Test_makeTransport(t *testing.T) {
+	registryName := "my.registry.name"
+
+	tests := []struct {
+		name  string
+		opts  *config.KanikoOptions
+		check func(*tls.Config, *mockedCertPool)
+	}{
+		{
+			name: "SkipTLSVerify set",
+			opts: &config.KanikoOptions{SkipTLSVerify: true},
+			check: func(config *tls.Config, pool *mockedCertPool) {
+				if !config.InsecureSkipVerify {
+					t.Errorf("makeTransport().TLSClientConfig.InsecureSkipVerify not set while SkipTLSVerify set")
+				}
+			},
+		},
+		{
+			name: "SkipTLSVerifyRegistries set with expected registry",
+			opts: &config.KanikoOptions{SkipTLSVerifyRegistries: []string{registryName}},
+			check: func(config *tls.Config, pool *mockedCertPool) {
+				if !config.InsecureSkipVerify {
+					t.Errorf("makeTransport().TLSClientConfig.InsecureSkipVerify not set while SkipTLSVerifyRegistries set with registry name")
+				}
+			},
+		},
+		{
+			name: "SkipTLSVerifyRegistries set with other registry",
+			opts: &config.KanikoOptions{SkipTLSVerifyRegistries: []string{fmt.Sprintf("other.%s", registryName)}},
+			check: func(config *tls.Config, pool *mockedCertPool) {
+				if config.InsecureSkipVerify {
+					t.Errorf("makeTransport().TLSClientConfig.InsecureSkipVerify set while SkipTLSVerifyRegistries not set with registry name")
+				}
+			},
+		},
+		{
+			name: "RegistriesCertificates set for registry",
+			opts: &config.KanikoOptions{RegistriesCertificates: map[string]string{registryName: "/path/to/the/certificate.cert"}},
+			check: func(config *tls.Config, pool *mockedCertPool) {
+				if len(pool.certificatesPath) != 1 || pool.certificatesPath[0] != "/path/to/the/certificate.cert" {
+					t.Errorf("makeTransport().RegistriesCertificates certificate not appended to system certificates")
+				}
+			},
+		},
+		{
+			name: "RegistriesCertificates set for another registry",
+			opts: &config.KanikoOptions{RegistriesCertificates: map[string]string{fmt.Sprintf("other.%s=", registryName): "/path/to/the/certificate.cert"}},
+			check: func(config *tls.Config, pool *mockedCertPool) {
+				if len(pool.certificatesPath) != 0 {
+					t.Errorf("makeTransport().RegistriesCertificates certificate appended to system certificates while added for other registry")
+				}
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var certificatesPath []string
+			certPool := mockedCertPool{
+				certificatesPath: certificatesPath,
+			}
+			var mockedSystemCertLoader systemCertLoader = func() CertPool {
+				return &certPool
+			}
+			transport := makeTransport(tt.opts, registryName, mockedSystemCertLoader)
+			tt.check(transport.(*http.Transport).TLSClientConfig, &certPool)
+		})
+	}
+}