Separate web UI into standalone metacrypt-web binary

The vault server holds in-memory unsealed state (KEK, engine keys) that
is lost on restart, requiring a full unseal ceremony. Previously the web
UI ran inside the vault process, so any UI change forced a restart and
re-unseal.

This change extracts the web UI into a separate metacrypt-web binary
that communicates with the vault over an authenticated gRPC connection.
The web server carries no sealed state and can be restarted freely.

- gen/metacrypt/v1/: generated Go bindings from proto/metacrypt/v1/
- internal/grpcserver/: full gRPC server implementation (System, Auth,
  Engine, PKI, Policy, ACME services) with seal/auth/admin interceptors
- internal/webserver/: web server with gRPC vault client; templates
  embedded via web/embed.go (no runtime web/ directory needed)
- cmd/metacrypt-web/: standalone binary entry point
- internal/config: added [web] section (listen_addr, vault_grpc, etc.)
- internal/server/routes.go: removed all web UI routes and handlers
- cmd/metacrypt/server.go: starts gRPC server alongside HTTP server
- Deploy: Dockerfile builds both binaries, docker-compose adds
  metacrypt-web service, new metacrypt-web.service systemd unit,
  Makefile gains proto/metacrypt-web targets

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/server/routes.go

@@ -1,24 +1,16 @@
 package server
 
 import (
-	"context"
-	"crypto/x509"
 	"encoding/json"
-	"encoding/pem"
 	"errors"
-	"fmt"
-	"html/template"
 	"io"
 	"net/http"
-	"path/filepath"
 	"strings"
-	"time"
 
 	"github.com/go-chi/chi/v5"
 
 	mcias "git.wntrmute.dev/kyle/mcias/clients/go"
 
-	"git.wntrmute.dev/kyle/metacrypt/internal/auth"
 	"git.wntrmute.dev/kyle/metacrypt/internal/crypto"
 	"git.wntrmute.dev/kyle/metacrypt/internal/engine"
 	"git.wntrmute.dev/kyle/metacrypt/internal/engine/ca"
@@ -27,25 +19,7 @@ import (
 )
 
 func (s *Server) registerRoutes(r chi.Router) {
-	// Static files.
-	r.Handle("/static/*", http.StripPrefix("/static/", http.FileServer(http.Dir("web/static"))))
-
-	// Web UI routes.
-	r.Get("/", s.handleWebRoot)
-	r.HandleFunc("/init", s.handleWebInit)
-	r.HandleFunc("/unseal", s.handleWebUnseal)
-	r.HandleFunc("/login", s.handleWebLogin)
-	r.Get("/dashboard", s.requireAuthWeb(s.handleWebDashboard))
-	r.Post("/dashboard/mount-ca", s.requireAuthWeb(s.handleWebDashboardMountCA))
-
-	r.Route("/pki", func(r chi.Router) {
-		r.Get("/", s.requireAuthWeb(s.handleWebPKI))
-		r.Post("/import-root", s.requireAuthWeb(s.handleWebImportRoot))
-		r.Post("/create-issuer", s.requireAuthWeb(s.handleWebCreateIssuer))
-		r.Get("/{issuer}", s.requireAuthWeb(s.handleWebPKIIssuer))
-	})
-
-	// API routes.
+	// REST API routes — web UI served by metacrypt-web.
 	r.Get("/v1/status", s.handleStatus)
 	r.Post("/v1/init", s.handleInit)
 	r.Post("/v1/unseal", s.handleUnseal)
@@ -67,7 +41,8 @@ func (s *Server) registerRoutes(r chi.Router) {
 
 	r.HandleFunc("/v1/policy/rules", s.requireAuth(s.handlePolicyRules))
 	r.HandleFunc("/v1/policy/rule", s.requireAuth(s.handlePolicyRule))
-	s.registerACMERoutes(r)}
+	s.registerACMERoutes(r)
+}
 
 // --- API Handlers ---
 
@@ -478,474 +453,6 @@ func (s *Server) getCAEngine(mountName string) (*ca.CAEngine, error) {
 	return caEng, nil
 }
 
-// findCAMount returns the name of the first CA engine mount.
-func (s *Server) findCAMount() (string, error) {
-	for _, m := range s.engines.ListMounts() {
-		if m.Type == engine.EngineTypeCA {
-			return m.Name, nil
-		}
-	}
-	return "", errors.New("no CA engine mounted")
-}
-
-// --- Web Handlers ---
-
-func (s *Server) handleWebRoot(w http.ResponseWriter, r *http.Request) {
-	state := s.seal.State()
-	switch state {
-	case seal.StateUninitialized:
-		http.Redirect(w, r, "/init", http.StatusFound)
-	case seal.StateSealed:
-		http.Redirect(w, r, "/unseal", http.StatusFound)
-	case seal.StateInitializing:
-		http.Redirect(w, r, "/init", http.StatusFound)
-	case seal.StateUnsealed:
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-	}
-}
-
-func (s *Server) handleWebInit(w http.ResponseWriter, r *http.Request) {
-	switch r.Method {
-	case http.MethodGet:
-		if s.seal.State() != seal.StateUninitialized {
-			http.Redirect(w, r, "/", http.StatusFound)
-			return
-		}
-		s.renderTemplate(w, "init.html", nil)
-	case http.MethodPost:
-		r.ParseForm()
-		password := r.FormValue("password")
-		if password == "" {
-			s.renderTemplate(w, "init.html", map[string]interface{}{"Error": "Password is required"})
-			return
-		}
-		params := crypto.Argon2Params{
-			Time:    s.cfg.Seal.Argon2Time,
-			Memory:  s.cfg.Seal.Argon2Memory,
-			Threads: s.cfg.Seal.Argon2Threads,
-		}
-		if err := s.seal.Initialize(r.Context(), []byte(password), params); err != nil {
-			s.renderTemplate(w, "init.html", map[string]interface{}{"Error": err.Error()})
-			return
-		}
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-	default:
-		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
-	}
-}
-
-func (s *Server) handleWebUnseal(w http.ResponseWriter, r *http.Request) {
-	switch r.Method {
-	case http.MethodGet:
-		state := s.seal.State()
-		if state == seal.StateUninitialized {
-			http.Redirect(w, r, "/init", http.StatusFound)
-			return
-		}
-		if state == seal.StateUnsealed {
-			http.Redirect(w, r, "/dashboard", http.StatusFound)
-			return
-		}
-		s.renderTemplate(w, "unseal.html", nil)
-	case http.MethodPost:
-		r.ParseForm()
-		password := r.FormValue("password")
-		if err := s.seal.Unseal([]byte(password)); err != nil {
-			msg := "Invalid password"
-			if err == seal.ErrRateLimited {
-				msg = "Too many attempts. Please wait 60 seconds."
-			}
-			s.renderTemplate(w, "unseal.html", map[string]interface{}{"Error": msg})
-			return
-		}
-		if err := s.engines.UnsealAll(r.Context()); err != nil {
-			s.logger.Error("engine unseal failed", "error", err)
-			s.renderTemplate(w, "unseal.html", map[string]interface{}{"Error": "Engine reload failed: " + err.Error()})
-			return
-		}
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-	default:
-		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
-	}
-}
-
-func (s *Server) handleWebLogin(w http.ResponseWriter, r *http.Request) {
-	if s.seal.State() != seal.StateUnsealed {
-		http.Redirect(w, r, "/", http.StatusFound)
-		return
-	}
-	switch r.Method {
-	case http.MethodGet:
-		s.renderTemplate(w, "login.html", nil)
-	case http.MethodPost:
-		r.ParseForm()
-		username := r.FormValue("username")
-		password := r.FormValue("password")
-		totpCode := r.FormValue("totp_code")
-		token, _, err := s.auth.Login(username, password, totpCode)
-		if err != nil {
-			s.renderTemplate(w, "login.html", map[string]interface{}{"Error": "Invalid credentials"})
-			return
-		}
-		http.SetCookie(w, &http.Cookie{
-			Name:     "metacrypt_token",
-			Value:    token,
-			Path:     "/",
-			HttpOnly: true,
-			Secure:   true,
-			SameSite: http.SameSiteStrictMode,
-		})
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-	default:
-		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
-	}
-}
-
-func (s *Server) handleWebDashboard(w http.ResponseWriter, r *http.Request) {
-	info := TokenInfoFromContext(r.Context())
-	mounts := s.engines.ListMounts()
-	s.renderTemplate(w, "dashboard.html", map[string]interface{}{
-		"Username": info.Username,
-		"IsAdmin":  info.IsAdmin,
-		"Roles":    info.Roles,
-		"Mounts":   mounts,
-		"State":    s.seal.State().String(),
-		"Version":  s.version,
-	})
-}
-
-func (s *Server) handleWebDashboardMountCA(w http.ResponseWriter, r *http.Request) {
-	info := TokenInfoFromContext(r.Context())
-	if !info.IsAdmin {
-		http.Error(w, "forbidden", http.StatusForbidden)
-		return
-	}
-
-	if err := r.ParseMultipartForm(1 << 20); err != nil {
-		r.ParseForm()
-	}
-
-	mountName := r.FormValue("name")
-	if mountName == "" {
-		s.renderDashboardWithError(w, r, info, "Mount name is required")
-		return
-	}
-
-	config := map[string]interface{}{}
-	if org := r.FormValue("organization"); org != "" {
-		config["organization"] = org
-	}
-
-	// Optional root CA import.
-	var certPEM, keyPEM string
-	if f, _, err := r.FormFile("cert_file"); err == nil {
-		defer f.Close()
-		data, _ := io.ReadAll(io.LimitReader(f, 1<<20))
-		certPEM = string(data)
-	}
-	if f, _, err := r.FormFile("key_file"); err == nil {
-		defer f.Close()
-		data, _ := io.ReadAll(io.LimitReader(f, 1<<20))
-		keyPEM = string(data)
-	}
-	if certPEM != "" && keyPEM != "" {
-		config["root_cert_pem"] = certPEM
-		config["root_key_pem"] = keyPEM
-	}
-
-	if err := s.engines.Mount(r.Context(), mountName, engine.EngineTypeCA, config); err != nil {
-		s.renderDashboardWithError(w, r, info, err.Error())
-		return
-	}
-
-	http.Redirect(w, r, "/pki", http.StatusFound)
-}
-
-func (s *Server) renderDashboardWithError(w http.ResponseWriter, _ *http.Request, info *auth.TokenInfo, errMsg string) {
-	mounts := s.engines.ListMounts()
-	s.renderTemplate(w, "dashboard.html", map[string]interface{}{
-		"Username":   info.Username,
-		"IsAdmin":    info.IsAdmin,
-		"Roles":      info.Roles,
-		"Mounts":     mounts,
-		"State":      s.seal.State().String(),
-		"MountError": errMsg,
-	})
-}
-
-func (s *Server) handleWebPKI(w http.ResponseWriter, r *http.Request) {
-	info := TokenInfoFromContext(r.Context())
-
-	mountName, err := s.findCAMount()
-	if err != nil {
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-		return
-	}
-
-	caEng, err := s.getCAEngine(mountName)
-	if err != nil {
-		http.Redirect(w, r, "/dashboard", http.StatusFound)
-		return
-	}
-
-	data := map[string]interface{}{
-		"Username":  info.Username,
-		"IsAdmin":   info.IsAdmin,
-		"MountName": mountName,
-	}
-
-	// Get root cert info.
-	rootPEM, err := caEng.GetRootCertPEM()
-	if err == nil && rootPEM != nil {
-		if cert, err := parsePEMCert(rootPEM); err == nil {
-			data["RootCN"] = cert.Subject.CommonName
-			data["RootOrg"] = strings.Join(cert.Subject.Organization, ", ")
-			data["RootNotBefore"] = cert.NotBefore.Format(time.RFC3339)
-			data["RootNotAfter"] = cert.NotAfter.Format(time.RFC3339)
-			data["RootExpired"] = time.Now().After(cert.NotAfter)
-			data["HasRoot"] = true
-		}
-	}
-
-	// Get issuers.
-	callerInfo := &engine.CallerInfo{
-		Username: info.Username,
-		Roles:    info.Roles,
-		IsAdmin:  info.IsAdmin,
-	}
-	resp, err := s.engines.HandleRequest(r.Context(), mountName, &engine.Request{
-		Operation:  "list-issuers",
-		CallerInfo: callerInfo,
-	})
-	if err == nil {
-		data["Issuers"] = resp.Data["issuers"]
-	}
-
-	s.renderTemplate(w, "pki.html", data)
-}
-
-func (s *Server) handleWebImportRoot(w http.ResponseWriter, r *http.Request) {
-	info := TokenInfoFromContext(r.Context())
-	if !info.IsAdmin {
-		http.Error(w, "forbidden", http.StatusForbidden)
-		return
-	}
-
-	mountName, err := s.findCAMount()
-	if err != nil {
-		http.Error(w, "no CA engine mounted", http.StatusNotFound)
-		return
-	}
-
-	if err := r.ParseMultipartForm(1 << 20); err != nil {
-		r.ParseForm()
-	}
-
-	certPEM := r.FormValue("cert_pem")
-	keyPEM := r.FormValue("key_pem")
-
-	// Also support file uploads.
-	if certPEM == "" {
-		if f, _, err := r.FormFile("cert_file"); err == nil {
-			defer f.Close()
-			data, _ := io.ReadAll(io.LimitReader(f, 1<<20))
-			certPEM = string(data)
-		}
-	}
-	if keyPEM == "" {
-		if f, _, err := r.FormFile("key_file"); err == nil {
-			defer f.Close()
-			data, _ := io.ReadAll(io.LimitReader(f, 1<<20))
-			keyPEM = string(data)
-		}
-	}
-
-	if certPEM == "" || keyPEM == "" {
-		s.renderPKIWithError(w, r, mountName, info, "Certificate and private key are required")
-		return
-	}
-
-	callerInfo := &engine.CallerInfo{
-		Username: info.Username,
-		Roles:    info.Roles,
-		IsAdmin:  info.IsAdmin,
-	}
-	_, err = s.engines.HandleRequest(r.Context(), mountName, &engine.Request{
-		Operation:  "import-root",
-		CallerInfo: callerInfo,
-		Data: map[string]interface{}{
-			"cert_pem": certPEM,
-			"key_pem":  keyPEM,
-		},
-	})
-	if err != nil {
-		s.renderPKIWithError(w, r, mountName, info, err.Error())
-		return
-	}
-
-	http.Redirect(w, r, "/pki", http.StatusFound)
-}
-
-func (s *Server) handleWebCreateIssuer(w http.ResponseWriter, r *http.Request) {
-	info := TokenInfoFromContext(r.Context())
-	if !info.IsAdmin {
-		http.Error(w, "forbidden", http.StatusForbidden)
-		return
-	}
-
-	mountName, err := s.findCAMount()
-	if err != nil {
-		http.Error(w, "no CA engine mounted", http.StatusNotFound)
-		return
-	}
-
-	r.ParseForm()
-
-	name := r.FormValue("name")
-	if name == "" {
-		s.renderPKIWithError(w, r, mountName, info, "Issuer name is required")
-		return
-	}
-
-	data := map[string]interface{}{
-		"name": name,
-	}
-	if v := r.FormValue("expiry"); v != "" {
-		data["expiry"] = v
-	}
-	if v := r.FormValue("max_ttl"); v != "" {
-		data["max_ttl"] = v
-	}
-	if v := r.FormValue("key_algorithm"); v != "" {
-		data["key_algorithm"] = v
-	}
-	if v := r.FormValue("key_size"); v != "" {
-		// Parse as float64 to match JSON number convention used by the engine.
-		var size float64
-		if _, err := fmt.Sscanf(v, "%f", &size); err == nil {
-			data["key_size"] = size
-		}
-	}
-
-	callerInfo := &engine.CallerInfo{
-		Username: info.Username,
-		Roles:    info.Roles,
-		IsAdmin:  info.IsAdmin,
-	}
-	_, err = s.engines.HandleRequest(r.Context(), mountName, &engine.Request{
-		Operation:  "create-issuer",
-		CallerInfo: callerInfo,
-		Data:       data,
-	})
-	if err != nil {
-		s.renderPKIWithError(w, r, mountName, info, err.Error())
-		return
-	}
-
-	http.Redirect(w, r, "/pki", http.StatusFound)
-}
-
-func (s *Server) handleWebPKIIssuer(w http.ResponseWriter, r *http.Request) {
-	mountName, err := s.findCAMount()
-	if err != nil {
-		http.Error(w, "no CA engine mounted", http.StatusNotFound)
-		return
-	}
-
-	issuerName := chi.URLParam(r, "issuer")
-	caEng, err := s.getCAEngine(mountName)
-	if err != nil {
-		http.Error(w, err.Error(), http.StatusNotFound)
-		return
-	}
-
-	certPEM, err := caEng.GetIssuerCertPEM(issuerName)
-	if err != nil {
-		http.Error(w, "issuer not found", http.StatusNotFound)
-		return
-	}
-
-	w.Header().Set("Content-Type", "application/x-pem-file")
-	w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=%s.pem", issuerName))
-	w.Write(certPEM)
-}
-
-func (s *Server) renderPKIWithError(w http.ResponseWriter, r *http.Request, mountName string, info *auth.TokenInfo, errMsg string) {
-	data := map[string]interface{}{
-		"Username":  info.Username,
-		"IsAdmin":   info.IsAdmin,
-		"MountName": mountName,
-		"Error":     errMsg,
-	}
-
-	// Try to load existing root info.
-	mount, merr := s.engines.GetMount(mountName)
-	if merr == nil && mount.Type == engine.EngineTypeCA {
-		if caEng, ok := mount.Engine.(*ca.CAEngine); ok {
-			rootPEM, err := caEng.GetRootCertPEM()
-			if err == nil && rootPEM != nil {
-				if cert, err := parsePEMCert(rootPEM); err == nil {
-					data["RootCN"] = cert.Subject.CommonName
-					data["RootOrg"] = strings.Join(cert.Subject.Organization, ", ")
-					data["RootNotBefore"] = cert.NotBefore.Format(time.RFC3339)
-					data["RootNotAfter"] = cert.NotAfter.Format(time.RFC3339)
-					data["RootExpired"] = time.Now().After(cert.NotAfter)
-					data["HasRoot"] = true
-				}
-			}
-		}
-	}
-
-	s.renderTemplate(w, "pki.html", data)
-}
-
-func parsePEMCert(pemData []byte) (*x509.Certificate, error) {
-	block, _ := pem.Decode(pemData)
-	if block == nil {
-		return nil, errors.New("no PEM block found")
-	}
-	return x509.ParseCertificate(block.Bytes)
-}
-
-// requireAuthWeb redirects to login for web pages instead of returning 401.
-func (s *Server) requireAuthWeb(next http.HandlerFunc) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		if s.seal.State() != seal.StateUnsealed {
-			http.Redirect(w, r, "/", http.StatusFound)
-			return
-		}
-		token := extractToken(r)
-		if token == "" {
-			http.Redirect(w, r, "/login", http.StatusFound)
-			return
-		}
-		info, err := s.auth.ValidateToken(token)
-		if err != nil {
-			http.Redirect(w, r, "/login", http.StatusFound)
-			return
-		}
-		ctx := r.Context()
-		ctx = context.WithValue(ctx, tokenInfoKey, info)
-		next(w, r.WithContext(ctx))
-	}
-}
-
-func (s *Server) renderTemplate(w http.ResponseWriter, name string, data interface{}) {
-	tmpl, err := template.ParseFiles(
-		filepath.Join("web", "templates", "layout.html"),
-		filepath.Join("web", "templates", name),
-	)
-	if err != nil {
-		s.logger.Error("parse template", "name", name, "error", err)
-		http.Error(w, "internal server error", http.StatusInternalServerError)
-		return
-	}
-	w.Header().Set("Content-Type", "text/html; charset=utf-8")
-	if err := tmpl.ExecuteTemplate(w, "layout", data); err != nil {
-		s.logger.Error("execute template", "name", name, "error", err)
-	}
-}
-
 func writeJSON(w http.ResponseWriter, status int, v interface{}) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(status)