Update dependencies

vendor/tailscale.com/clientupdate/distsign/roots.go

@@ -0,0 +1,54 @@
+// Copyright (c) Tailscale Inc & AUTHORS
+// SPDX-License-Identifier: BSD-3-Clause
+
+package distsign
+
+import (
+	"crypto/ed25519"
+	"embed"
+	"errors"
+	"fmt"
+	"path"
+	"path/filepath"
+	"sync"
+)
+
+//go:embed roots
+var rootsFS embed.FS
+
+var roots = sync.OnceValue(func() []ed25519.PublicKey {
+	roots, err := parseRoots()
+	if err != nil {
+		panic(err)
+	}
+	return roots
+})
+
+func parseRoots() ([]ed25519.PublicKey, error) {
+	files, err := rootsFS.ReadDir("roots")
+	if err != nil {
+		return nil, err
+	}
+	var keys []ed25519.PublicKey
+	for _, f := range files {
+		if !f.Type().IsRegular() {
+			continue
+		}
+		if filepath.Ext(f.Name()) != ".pem" {
+			continue
+		}
+		raw, err := rootsFS.ReadFile(path.Join("roots", f.Name()))
+		if err != nil {
+			return nil, err
+		}
+		key, err := parseSinglePublicKey(raw, pemTypeRootPublic)
+		if err != nil {
+			return nil, fmt.Errorf("parsing root key %q: %w", f.Name(), err)
+		}
+		keys = append(keys, key)
+	}
+	if len(keys) == 0 {
+		return nil, errors.New("no embedded root keys, please check clientupdate/distsign/roots/")
+	}
+	return keys, nil
+}