jail: add support for hostname

samuelkarp · samuelkarp · commit 658737c7a87d · 2022-06-20T15:17:15.000-07:00
diff --git a/README.md b/README.md
@@ -27,6 +27,7 @@ runj currently supports the following parts of the OCI runtime spec:
   - Process args
   - Process environment
   - Process terminal
+  - Hostname
   - Mounts
 
 ## Getting started
diff --git a/cmd/runj/create.go b/cmd/runj/create.go
@@ -162,8 +162,9 @@ written`)
 		}
 		var confPath string
 		confPath, err = jail.CreateConfig(&jail.Config{
-			Name: id,
-			Root: rootPath,
+			Name:     id,
+			Root:     rootPath,
+			Hostname: ociConfig.Hostname,
 		})
 		if err != nil {
 			return err
diff --git a/jail/conf.go b/jail/conf.go
@@ -14,6 +14,9 @@ const (
 	confName       = "jail.conf"
 	configTemplate = `{{ .Name }} {
   path = "{{ .Root }}";
+{{- if ne .Hostname "" }}
+  host.hostname = "{{.Hostname}}";
+{{- end }}
   persist;
 }
 `
diff --git a/jail/conf_test.go b/jail/conf_test.go
@@ -1,20 +1,40 @@
 package jail
 
 import (
+	"fmt"
 	"io/ioutil"
+	"path/filepath"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
-func TestRenderConfigBasic(t *testing.T) {
-	const (
-		id   = "basic"
-		path = "/tmp/test/basic/root"
-	)
-	expected, err := ioutil.ReadFile("testdata/basic.conf")
-	assert.NoError(t, err, "test data")
-	actual, err := renderConfig(&Config{Name: id, Root: path})
-	assert.NoError(t, err, "render")
-	assert.Equal(t, string(expected), actual)
+func TestRenderConfigGolden(t *testing.T) {
+	tests := []struct {
+		// name is both used as the subtest name and is the name of the golden data file in testdata
+		name   string
+		config Config
+	}{{
+		"basic",
+		Config{
+			Name: "basic",
+			Root: "/tmp/test/basic/root",
+		},
+	}, {
+		"hostname",
+		Config{
+			Name:     "hostname",
+			Root:     "/tmp/test/hostname/root",
+			Hostname: "test.hostname.example.com",
+		},
+	}}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			expected, err := ioutil.ReadFile(filepath.Join("testdata", fmt.Sprintf("%s.conf", tc.name)))
+			assert.NoError(t, err, "test data")
+			actual, err := renderConfig(&tc.config)
+			assert.NoError(t, err, "render")
+			assert.Equal(t, string(expected), actual)
+		})
+	}
 }
diff --git a/jail/testdata/hostname.conf b/jail/testdata/hostname.conf
@@ -0,0 +1,5 @@
+hostname {
+  path = "/tmp/test/hostname/root";
+  host.hostname = "test.hostname.example.com";
+  persist;
+}
diff --git a/runtimespec/config.go b/runtimespec/config.go
@@ -30,11 +30,9 @@ type Spec struct {
 	// Root configures the container's root filesystem.
 	Root *Root `json:"root,omitempty"`
 
-	// Modification by Samuel Karp
-	/*
-		// Hostname configures the container's hostname.
-		Hostname string `json:"hostname,omitempty"`
-	*/
+	// Hostname configures the container's hostname.
+	Hostname string `json:"hostname,omitempty"`
+
 	// Mounts configures additional mounts (on top of Root).
 	Mounts []Mount `json:"mounts,omitempty"`
 	/*

Original file line number	Diff line number	Diff line change
`@@ -14,6 +14,9 @@ const (`
`14`	`14`	`confName = "jail.conf"`
`15`	`15`	configTemplate = `{{ .Name }} {
`16`	`16`	`path = "{{ .Root }}";`
	`17`	`+{{- if ne .Hostname "" }}`
	`18`	`+ host.hostname = "{{.Hostname}}";`
	`19`	`+{{- end }}`
`17`	`20`	`persist;`
`18`	`21`	`}`
`19`	`22`	`