Fix IPv6 host aliases for kubernetes (#2992)

Closes #2991


[Tests](https://github.com/woodpecker-ci/woodpecker/pull/2993#issuecomment-1868048169)

---------

Co-authored-by: 6543 <6543@obermui.de>

pipeline/backend/docker/convert.go

@@ -88,8 +88,12 @@ func toHostConfig(step *types.Step) *container.HostConfig {
 	if len(step.DNSSearch) != 0 {
 		config.DNSSearch = step.DNSSearch
 	}
+	extraHosts := []string{}
+	for _, hostAlias := range step.ExtraHosts {
+		extraHosts = append(extraHosts, hostAlias.Name+":"+hostAlias.IP)
+	}
 	if len(step.ExtraHosts) != 0 {
-		config.ExtraHosts = step.ExtraHosts
+		config.ExtraHosts = extraHosts
 	}
 	if len(step.Devices) != 0 {
 		config.Devices = toDev(step.Devices)

pipeline/backend/kubernetes/kubernetes.go

@@ -20,7 +20,6 @@ import (
 	"io"
 	"os"
 	"runtime"
-	"strings"
 	"time"
 
 	"github.com/rs/zerolog/log"
@@ -166,8 +165,7 @@ func (e *kube) SetupWorkflow(ctx context.Context, conf *types.Config, taskUUID s
 		}
 	}
 
-	extraHosts := []string{}
-
+	extraHosts := []types.HostAlias{}
 	for _, stage := range conf.Stages {
 		if stage.Alias == "services" {
 			for _, step := range stage.Steps {
@@ -175,12 +173,12 @@ func (e *kube) SetupWorkflow(ctx context.Context, conf *types.Config, taskUUID s
 				if err != nil {
 					return err
 				}
-				extraHosts = append(extraHosts, step.Networks[0].Aliases[0]+":"+svc.Spec.ClusterIP)
+				hostAlias := types.HostAlias{Name: step.Networks[0].Aliases[0], IP: svc.Spec.ClusterIP}
+				extraHosts = append(extraHosts, hostAlias)
 			}
 		}
 	}
-
-	log.Trace().Msgf("Adding extra hosts: %s", strings.Join(extraHosts, ", "))
+	log.Trace().Msgf("Adding extra hosts: %v", extraHosts)
 	for _, stage := range conf.Stages {
 		for _, step := range stage.Steps {
 			step.ExtraHosts = extraHosts

pipeline/backend/kubernetes/pod.go

@@ -36,17 +36,16 @@ const (
 
 func mkPod(namespace, name, image, workDir, goos, serviceAccountName string,
 	pool, privileged bool,
-	commands, vols, extraHosts []string,
+	commands, vols []string,
 	labels, annotations, env, nodeSelector map[string]string,
-	tolerations []types.Toleration, resources types.Resources,
+	extraHosts []types.HostAlias, tolerations []types.Toleration, resources types.Resources,
 	securityContext *types.SecurityContext, securityContextConfig SecurityContextConfig,
 ) (*v1.Pod, error) {
 	var err error
 
 	meta := podMeta(name, namespace, labels, annotations)
 
-	spec, err := podSpec(serviceAccountName, vols, extraHosts, env,
-		nodeSelector, tolerations, securityContext, securityContextConfig)
+	spec, err := podSpec(serviceAccountName, vols, env, nodeSelector, extraHosts, tolerations, securityContext, securityContextConfig)
 	if err != nil {
 		return nil, err
 	}
@@ -86,7 +85,8 @@ func podMeta(name, namespace string, labels, annotations map[string]string) meta
 	return meta
 }
 
-func podSpec(serviceAccountName string, vols, extraHosts []string, env, backendNodeSelector map[string]string, backendTolerations []types.Toleration,
+func podSpec(serviceAccountName string, vols []string, env, backendNodeSelector map[string]string,
+	extraHosts []types.HostAlias, backendTolerations []types.Toleration,
 	securityContext *types.SecurityContext, securityContextConfig SecurityContextConfig,
 ) (v1.PodSpec, error) {
 	var err error
@@ -195,7 +195,7 @@ func volumeMount(name, path string) v1.VolumeMount {
 }
 
 // Here is the service IPs (placed in /etc/hosts in the Pod)
-func hostAliases(extraHosts []string) []v1.HostAlias {
+func hostAliases(extraHosts []types.HostAlias) []v1.HostAlias {
 	hostAliases := []v1.HostAlias{}
 	for _, extraHost := range extraHosts {
 		hostAlias := hostAlias(extraHost)
@@ -204,11 +204,10 @@ func hostAliases(extraHosts []string) []v1.HostAlias {
 	return hostAliases
 }
 
-func hostAlias(extraHost string) v1.HostAlias {
-	host := strings.Split(extraHost, ":")
+func hostAlias(extraHost types.HostAlias) v1.HostAlias {
 	return v1.HostAlias{
-		IP:        host[1],
-		Hostnames: []string{host[0]},
+		IP:        extraHost.IP,
+		Hostnames: []string{extraHost.Name},
 	}
 }
 
@@ -358,9 +357,9 @@ func startPod(ctx context.Context, engine *kube, step *types.Step) (*v1.Pod, err
 
 	pod, err := mkPod(engine.config.Namespace, podName, step.Image, step.WorkingDir, engine.goos, step.BackendOptions.Kubernetes.ServiceAccountName,
 		step.Pull, step.Privileged,
-		step.Commands, step.Volumes, step.ExtraHosts,
+		step.Commands, step.Volumes,
 		engine.config.PodLabels, engine.config.PodAnnotations, step.Environment, step.BackendOptions.Kubernetes.NodeSelector,
-		step.BackendOptions.Kubernetes.Tolerations, step.BackendOptions.Kubernetes.Resources, step.BackendOptions.Kubernetes.SecurityContext, engine.config.SecurityContext)
+		step.ExtraHosts, step.BackendOptions.Kubernetes.Tolerations, step.BackendOptions.Kubernetes.Resources, step.BackendOptions.Kubernetes.SecurityContext, engine.config.SecurityContext)
 	if err != nil {
 		return nil, err
 	}

pipeline/backend/kubernetes/pod_test.go

@@ -108,9 +108,9 @@ func TestTinyPod(t *testing.T) {
 
 	pod, err := mkPod("woodpecker", "wp-01he8bebctabr3kgk0qj36d2me-0", "gradle:8.4.0-jdk21", "/woodpecker/src", "linux/amd64", "",
 		false, false,
-		[]string{"gradle build"}, []string{"workspace:/woodpecker/src"}, nil,
+		[]string{"gradle build"}, []string{"workspace:/woodpecker/src"},
 		nil, nil, map[string]string{"CI": "woodpecker"}, nil,
-		nil,
+		nil, nil,
 		types.Resources{Requests: nil, Limits: nil}, nil, SecurityContextConfig{},
 	)
 	assert.NoError(t, err)
@@ -228,17 +228,27 @@ func TestFullPod(t *testing.T) {
 					"hostnames": [
 						"cloudflare"
 					]
+				},
+				{
+					"ip": "2606:4700:4700::64",
+					"hostnames": [
+						"cf.v6"
+					]
 				}
 			]
 		},
 		"status": {}
 	}`
 
+	hostAliases := []types.HostAlias{
+		{Name: "cloudflare", IP: "1.1.1.1"},
+		{Name: "cf.v6", IP: "2606:4700:4700::64"},
+	}
 	pod, err := mkPod("woodpecker", "wp-01he8bebctabr3kgk0qj36d2me-0", "meltwater/drone-cache", "/woodpecker/src", "linux/amd64", "wp-svc-acc",
 		true, true,
-		[]string{"go get", "go test"}, []string{"woodpecker-cache:/woodpecker/src/cache"}, []string{"cloudflare:1.1.1.1"},
+		[]string{"go get", "go test"}, []string{"woodpecker-cache:/woodpecker/src/cache"},
 		map[string]string{"app": "test"}, map[string]string{"apparmor.security": "runtime/default"}, map[string]string{"CGO": "0"}, map[string]string{"storage": "ssd"},
-		[]types.Toleration{{Key: "net-port", Value: "100Mbit", Effect: types.TaintEffectNoSchedule}},
+		hostAliases, []types.Toleration{{Key: "net-port", Value: "100Mbit", Effect: types.TaintEffectNoSchedule}},
 		types.Resources{Requests: map[string]string{"memory": "128Mi", "cpu": "1000m"}, Limits: map[string]string{"memory": "256Mi", "cpu": "2"}},
 		&types.SecurityContext{Privileged: newBool(true), RunAsNonRoot: newBool(true), RunAsUser: newInt64(101), RunAsGroup: newInt64(101), FSGroup: newInt64(101)},
 		SecurityContextConfig{RunAsNonRoot: false},

pipeline/backend/types/network.go

@@ -18,3 +18,8 @@ package types
 type Network struct {
 	Name string `json:"name,omitempty"`
 }
+
+type HostAlias struct {
+	Name string `json:"name,omitempty"`
+	IP   string `json:"ip,omitempty"`
+}

pipeline/backend/types/step.go

@@ -28,7 +28,7 @@ type Step struct {
 	Environment    map[string]string `json:"environment,omitempty"`
 	Entrypoint     []string          `json:"entrypoint,omitempty"`
 	Commands       []string          `json:"commands,omitempty"`
-	ExtraHosts     []string          `json:"extra_hosts,omitempty"`
+	ExtraHosts     []HostAlias       `json:"extra_hosts,omitempty"`
 	Volumes        []string          `json:"volumes,omitempty"`
 	Tmpfs          []string          `json:"tmpfs,omitempty"`
 	Devices        []string          `json:"devices,omitempty"`

pipeline/frontend/yaml/compiler/compiler_test.go

@@ -82,14 +82,15 @@ func TestCompilerCompile(t *testing.T) {
 		Name:  "test_clone",
 		Alias: "clone",
 		Steps: []*backend_types.Step{{
-			Name:      "test_clone",
-			Alias:     "clone",
-			Type:      backend_types.StepTypeClone,
-			Image:     constant.DefaultCloneImage,
-			OnSuccess: true,
-			Failure:   "fail",
-			Volumes:   []string{defaultVolumes[0].Name + ":"},
-			Networks:  []backend_types.Conn{{Name: "test_default", Aliases: []string{"clone"}}},
+			Name:       "test_clone",
+			Alias:      "clone",
+			Type:       backend_types.StepTypeClone,
+			Image:      constant.DefaultCloneImage,
+			OnSuccess:  true,
+			Failure:    "fail",
+			Volumes:    []string{defaultVolumes[0].Name + ":"},
+			Networks:   []backend_types.Conn{{Name: "test_default", Aliases: []string{"clone"}}},
+			ExtraHosts: []backend_types.HostAlias{},
 		}},
 	}
 
@@ -126,14 +127,15 @@ func TestCompilerCompile(t *testing.T) {
 				Name:  "test_stage_0",
 				Alias: "dummy",
 				Steps: []*backend_types.Step{{
-					Name:      "test_step_0",
-					Alias:     "dummy",
-					Type:      backend_types.StepTypePlugin,
-					Image:     "dummy_img",
-					OnSuccess: true,
-					Failure:   "fail",
-					Volumes:   []string{defaultVolumes[0].Name + ":"},
-					Networks:  []backend_types.Conn{{Name: "test_default", Aliases: []string{"dummy"}}},
+					Name:       "test_step_0",
+					Alias:      "dummy",
+					Type:       backend_types.StepTypePlugin,
+					Image:      "dummy_img",
+					OnSuccess:  true,
+					Failure:    "fail",
+					Volumes:    []string{defaultVolumes[0].Name + ":"},
+					Networks:   []backend_types.Conn{{Name: "test_default", Aliases: []string{"dummy"}}},
+					ExtraHosts: []backend_types.HostAlias{},
 				}},
 			}},
 		},
@@ -161,39 +163,42 @@ func TestCompilerCompile(t *testing.T) {
 				Name:  "test_stage_0",
 				Alias: "echo env",
 				Steps: []*backend_types.Step{{
-					Name:      "test_step_0",
-					Alias:     "echo env",
-					Type:      backend_types.StepTypeCommands,
-					Image:     "bash",
-					Commands:  []string{"env"},
-					OnSuccess: true,
-					Failure:   "fail",
-					Volumes:   []string{defaultVolumes[0].Name + ":"},
-					Networks:  []backend_types.Conn{{Name: "test_default", Aliases: []string{"echo env"}}},
+					Name:       "test_step_0",
+					Alias:      "echo env",
+					Type:       backend_types.StepTypeCommands,
+					Image:      "bash",
+					Commands:   []string{"env"},
+					OnSuccess:  true,
+					Failure:    "fail",
+					Volumes:    []string{defaultVolumes[0].Name + ":"},
+					Networks:   []backend_types.Conn{{Name: "test_default", Aliases: []string{"echo env"}}},
+					ExtraHosts: []backend_types.HostAlias{},
 				}},
 			}, {
 				Name:  "test_stage_1",
 				Alias: "parallel echo 1",
 				Steps: []*backend_types.Step{{
-					Name:      "test_step_1",
-					Alias:     "parallel echo 1",
-					Type:      backend_types.StepTypeCommands,
-					Image:     "bash",
-					Commands:  []string{"echo 1"},
-					OnSuccess: true,
-					Failure:   "fail",
-					Volumes:   []string{defaultVolumes[0].Name + ":"},
-					Networks:  []backend_types.Conn{{Name: "test_default", Aliases: []string{"parallel echo 1"}}},
+					Name:       "test_step_1",
+					Alias:      "parallel echo 1",
+					Type:       backend_types.StepTypeCommands,
+					Image:      "bash",
+					Commands:   []string{"echo 1"},
+					OnSuccess:  true,
+					Failure:    "fail",
+					Volumes:    []string{defaultVolumes[0].Name + ":"},
+					Networks:   []backend_types.Conn{{Name: "test_default", Aliases: []string{"parallel echo 1"}}},
+					ExtraHosts: []backend_types.HostAlias{},
 				}, {
-					Name:      "test_step_2",
-					Alias:     "parallel echo 2",
-					Type:      backend_types.StepTypeCommands,
-					Image:     "bash",
-					Commands:  []string{"echo 2"},
-					OnSuccess: true,
-					Failure:   "fail",
-					Volumes:   []string{defaultVolumes[0].Name + ":"},
-					Networks:  []backend_types.Conn{{Name: "test_default", Aliases: []string{"parallel echo 2"}}},
+					Name:       "test_step_2",
+					Alias:      "parallel echo 2",
+					Type:       backend_types.StepTypeCommands,
+					Image:      "bash",
+					Commands:   []string{"echo 2"},
+					OnSuccess:  true,
+					Failure:    "fail",
+					Volumes:    []string{defaultVolumes[0].Name + ":"},
+					Networks:   []backend_types.Conn{{Name: "test_default", Aliases: []string{"parallel echo 2"}}},
+					ExtraHosts: []backend_types.HostAlias{},
 				}},
 			}},
 		},

pipeline/frontend/yaml/compiler/convert.go

@@ -55,6 +55,16 @@ func (c *Compiler) createProcess(name string, container *yaml_types.Container, s
 		})
 	}
 
+	extraHosts := make([]backend_types.HostAlias, len(container.ExtraHosts))
+	for i, extraHost := range container.ExtraHosts {
+		name, ip, ok := strings.Cut(extraHost, ":")
+		if !ok {
+			return nil, &ErrExtraHostFormat{host: extraHost}
+		}
+		extraHosts[i].Name = name
+		extraHosts[i].IP = ip
+	}
+
 	var volumes []string
 	if !c.local {
 		volumes = append(volumes, workspace)
@@ -173,7 +183,7 @@ func (c *Compiler) createProcess(name string, container *yaml_types.Container, s
 		WorkingDir:     workingdir,
 		Environment:    environment,
 		Commands:       container.Commands,
-		ExtraHosts:     container.ExtraHosts,
+		ExtraHosts:     extraHosts,
 		Volumes:        volumes,
 		Tmpfs:          container.Tmpfs,
 		Devices:        container.Devices,

pipeline/frontend/yaml/compiler/errors.go

@@ -0,0 +1,30 @@
+// Copyright 2023 Woodpecker 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 compiler
+
+import "fmt"
+
+type ErrExtraHostFormat struct {
+	host string
+}
+
+func (err *ErrExtraHostFormat) Error() string {
+	return fmt.Sprintf("extra host %s is in wrong format", err.host)
+}
+
+func (*ErrExtraHostFormat) Is(target error) bool {
+	_, ok := target.(*ErrExtraHostFormat) //nolint:errorlint
+	return ok
+}

pipeline/frontend/yaml/types/container_test.go

@@ -45,6 +45,7 @@ environment:
 extra_hosts:
  - somehost:162.242.195.82
  - otherhost:50.31.209.229
+ - ipv6:2001:db8::10
 name: my-build-container
 network_mode: bridge
 networks:
@@ -84,7 +85,7 @@ func TestUnmarshalContainer(t *testing.T) {
 		DNS:          base.StringOrSlice{"8.8.8.8"},
 		DNSSearch:    base.StringOrSlice{"example.com"},
 		Environment:  base.SliceOrMap{"RACK_ENV": "development", "SHOW": "true"},
-		ExtraHosts:   []string{"somehost:162.242.195.82", "otherhost:50.31.209.229"},
+		ExtraHosts:   []string{"somehost:162.242.195.82", "otherhost:50.31.209.229", "ipv6:2001:db8::10"},
 		Image:        "golang:latest",
 		MemLimit:     base.MemStringOrInt(1024),
 		MemSwapLimit: base.MemStringOrInt(1024),