Add timezone validation

pkg/limayaml/defaults.go

@@ -135,26 +135,6 @@ func MACAddress(uniqueID string) string {
 	return hw.String()
 }
 
-func hostTimeZone() string {
-	// WSL2 will automatically set the timezone
-	if runtime.GOOS != "windows" {
-		tz, err := os.ReadFile("/etc/timezone")
-		if err == nil {
-			return strings.TrimSpace(string(tz))
-		}
-		zoneinfoFile, err := filepath.EvalSymlinks("/etc/localtime")
-		if err == nil {
-			for baseDir := filepath.Dir(zoneinfoFile); baseDir != "/"; baseDir = filepath.Dir(baseDir) {
-				if _, err = os.Stat(filepath.Join(baseDir, "Etc/UTC")); err == nil {
-					return strings.TrimPrefix(zoneinfoFile, baseDir+"/")
-				}
-			}
-			logrus.Warnf("could not locate zoneinfo directory from %q", zoneinfoFile)
-		}
-	}
-	return ""
-}
-
 func defaultCPUs() int {
 	const x = 4
 	if hostCPUs := runtime.NumCPU(); hostCPUs < x {

pkg/limayaml/defaults_unix.go

@@ -0,0 +1,58 @@
+//go:build !windows
+
+// SPDX-FileCopyrightText: Copyright The Lima Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package limayaml
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/sirupsen/logrus"
+)
+
+func hostTimeZone() string {
+	if tzBytes, err := os.ReadFile("/etc/timezone"); err == nil {
+		if tz := strings.TrimSpace(string(tzBytes)); tz != "" {
+			if _, err := time.LoadLocation(tz); err != nil {
+				logrus.Warnf("invalid timezone found in /etc/timezone: %v", err)
+			} else {
+				return tz
+			}
+		}
+	}
+
+	if zoneinfoFile, err := filepath.EvalSymlinks("/etc/localtime"); err == nil {
+		if tz, err := extractTZFromPath(zoneinfoFile); err != nil {
+			logrus.Warnf("failed to extract timezone from %s: %v", zoneinfoFile, err)
+		} else {
+			return tz
+		}
+	}
+
+	logrus.Warn("unable to determine host timezone, falling back to default value")
+	return ""
+}
+
+func extractTZFromPath(zoneinfoFile string) (string, error) {
+	if zoneinfoFile == "" {
+		return "", errors.New("invalid zoneinfo file path")
+	}
+
+	if _, err := os.Stat(zoneinfoFile); os.IsNotExist(err) {
+		return "", fmt.Errorf("zoneinfo file does not exist: %s", zoneinfoFile)
+	}
+
+	for dir := filepath.Dir(zoneinfoFile); dir != filepath.Dir(dir); dir = filepath.Dir(dir) {
+		if _, err := os.Stat(filepath.Join(dir, "Etc", "UTC")); err == nil {
+			return filepath.Rel(dir, zoneinfoFile)
+		}
+	}
+
+	return "", errors.New("timezone base directory not found")
+}

pkg/limayaml/defaults_unix_test.go

@@ -0,0 +1,75 @@
+//go:build !windows
+
+// SPDX-FileCopyrightText: Copyright The Lima Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package limayaml
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"gotest.tools/v3/assert"
+)
+
+func TestExtractTimezoneFromPath(t *testing.T) {
+	tmpDir := t.TempDir()
+
+	// Create test timezone directory structure
+	assert.NilError(t, os.MkdirAll(filepath.Join(tmpDir, "Etc"), 0o755))
+	assert.NilError(t, os.WriteFile(filepath.Join(tmpDir, "Etc", "UTC"), []byte{}, 0o644))
+	assert.NilError(t, os.WriteFile(filepath.Join(tmpDir, "UTC"), []byte{}, 0o644))
+	assert.NilError(t, os.MkdirAll(filepath.Join(tmpDir, "Antarctica"), 0o755))
+	assert.NilError(t, os.WriteFile(filepath.Join(tmpDir, "Antarctica", "Troll"), []byte{}, 0o644))
+
+	tests := []struct {
+		name    string
+		path    string
+		want    string
+		wantErr bool
+	}{
+		{
+			"valid_timezone",
+			filepath.Join(tmpDir, "Antarctica", "Troll"),
+			"Antarctica/Troll",
+			false,
+		},
+		{
+			"root_level_zone",
+			filepath.Join(tmpDir, "UTC"),
+			"UTC",
+			false,
+		},
+		{
+			"outside_zoneinfo",
+			"/tmp/somefile",
+			"",
+			true,
+		},
+		{
+			"empty_path",
+			"",
+			"",
+			true,
+		},
+		{
+			"nonexistent_file",
+			filepath.Join(tmpDir, "Invalid", "Zone"),
+			"",
+			true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := extractTZFromPath(tt.path)
+			if tt.wantErr {
+				assert.Assert(t, err != nil, "expected error but got none")
+			} else {
+				assert.NilError(t, err)
+			}
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}

pkg/limayaml/defaults_windows.go

@@ -0,0 +1,11 @@
+//go:build windows
+
+// SPDX-FileCopyrightText: Copyright The Lima Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package limayaml
+
+func hostTimeZone() string {
+	// WSL2 will automatically set the timezone
+	return ""
+}