pki: Add trust subcommand to install root cert (closes caddyserver#3204)

caddy.go

@@ -372,7 +372,7 @@ func run(newCfg *Config, start bool) error {
 		}
 
 		if newCfg.storage == nil {
-			newCfg.storage = &certmagic.FileStorage{Path: AppDataDir()}
+			newCfg.storage = DefaultStorage
 		}
 		certmagic.Default.Storage = newCfg.storage
 

modules/caddypki/ca.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/caddyserver/caddy/v2"
 	"github.com/caddyserver/certmagic"
+	"github.com/smallstep/truststore"
 	"go.uber.org/zap"
 )
 
@@ -323,6 +324,27 @@ func (ca CA) newReplacer() *caddy.Replacer {
 	return repl
 }
 
+// installRoot installs this CA's root certificate into the
+// local trust store(s) if it is not already trusted. The CA
+// must already be provisioned.
+func (ca CA) installRoot() error {
+	// avoid password prompt if already trusted
+	if trusted(ca.root) {
+		ca.log.Info("root certificate is already trusted by system",
+			zap.String("path", ca.rootCertPath))
+		return nil
+	}
+
+	ca.log.Warn("installing root certificate (you might be prompted for password)",
+		zap.String("path", ca.rootCertPath))
+
+	return truststore.Install(ca.root,
+		truststore.WithDebug(),
+		truststore.WithFirefox(),
+		truststore.WithJava(),
+	)
+}
+
 const (
 	defaultCAID                   = "local"
 	defaultCAName                 = "Caddy Local Authority"

modules/caddypki/command.go

@@ -15,6 +15,7 @@
 package caddypki
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"os"
@@ -26,6 +27,25 @@ import (
 )
 
 func init() {
+	caddycmd.RegisterCommand(caddycmd.Command{
+		Name:  "trust",
+		Func:  cmdTrust,
+		Short: "Installs a CA certificate into local trust stores",
+		Long: `
+Adds a root certificate into the local trust stores. Intended for
+development environments only.
+
+Since Caddy will install its root certificates into the local trust
+stores automatically when they are first generated, this command is
+only necessary if you need to pre-install the certificates before
+using them; for example, if you have elevated privileges at one
+point but not later, you will want to use this command so that a
+password prompt is not required later.
+
+This command installs the root certificate only for Caddy's
+default CA.`,
+	})
+
 	caddycmd.RegisterCommand(caddycmd.Command{
 		Name:  "untrust",
 		Func:  cmdUntrust,
@@ -57,6 +77,30 @@ If no flags are specified, --ca=local is assumed.`,
 	})
 }
 
+func cmdTrust(fs caddycmd.Flags) (int, error) {
+	// we have to create a sort of dummy context so that
+	// the CA can provision itself...
+	ctx, cancel := caddy.NewContext(caddy.Context{Context: context.Background()})
+	defer cancel()
+
+	// provision the CA, which generates and stores a root
+	// certificate if one doesn't already exist in storage
+	ca := CA{
+		storage: caddy.DefaultStorage,
+	}
+	err := ca.Provision(ctx, defaultCAID, caddy.Log())
+	if err != nil {
+		return caddy.ExitCodeFailedStartup, err
+	}
+
+	err = ca.installRoot()
+	if err != nil {
+		return caddy.ExitCodeFailedStartup, err
+	}
+
+	return caddy.ExitCodeSuccess, nil
+}
+
 func cmdUntrust(fs caddycmd.Flags) (int, error) {
 	ca := fs.String("ca")
 	cert := fs.String("cert")

modules/caddypki/pki.go

@@ -18,7 +18,6 @@ import (
 	"fmt"
 
 	"github.com/caddyserver/caddy/v2"
-	"github.com/smallstep/truststore"
 	"go.uber.org/zap"
 )
 
@@ -71,30 +70,15 @@ func (p *PKI) Start() error {
 	// install roots to trust store, if not disabled
 	for _, ca := range p.CAs {
 		if ca.InstallTrust != nil && !*ca.InstallTrust {
-			ca.log.Warn("root certificate trust store installation disabled; local clients may show warnings",
+			ca.log.Warn("root certificate trust store installation disabled; unconfigured clients may show warnings",
 				zap.String("path", ca.rootCertPath))
 			continue
 		}
 
-		// avoid password prompt if already trusted
-		if trusted(ca.root) {
-			ca.log.Info("root certificate is already trusted by system",
-				zap.String("path", ca.rootCertPath))
-			continue
-		}
-
-		ca.log.Warn("trusting root certificate (you might be prompted for password)",
-			zap.String("path", ca.rootCertPath))
-
-		err := truststore.Install(ca.root,
-			truststore.WithDebug(),
-			truststore.WithFirefox(),
-			truststore.WithJava(),
-		)
-		if err != nil {
+		if err := ca.installRoot(); err != nil {
 			// could be some system dependencies that are missing;
 			// shouldn't totally prevent startup, but we should log it
-			p.log.Error("failed to install root certificate",
+			ca.log.Error("failed to install root certificate",
 				zap.Error(err),
 				zap.String("certificate_file", ca.rootCertPath))
 		}

storage.go

@@ -155,3 +155,6 @@ func AppDataDir() string {
 
 // ConfigAutosavePath is the default path to which the last config will be persisted.
 var ConfigAutosavePath = filepath.Join(AppConfigDir(), "autosave.json")
+
+// DefaultStorage is Caddy's default storage module.
+var DefaultStorage = &certmagic.FileStorage{Path: AppDataDir()}