server auth

apps/server/internal/httpserver/middleware.go

@@ -5,9 +5,12 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/go-chi/chi/v5/middleware"
+
+	"github.com/tim/cairnquire/apps/server/internal/auth"
 )
 
 func (s *Server) timeoutExceptWebSocket(timeout time.Duration) func(http.Handler) http.Handler {
@@ -49,6 +52,88 @@ func (s *Server) securityHeaders(next http.Handler) http.Handler {
 	})
 }
 
+func (s *Server) authMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		principal, ok := s.authenticateRequest(r)
+		if ok {
+			r = r.WithContext(withPrincipal(r.Context(), principal))
+		}
+
+		required, protected := requiredScopeForPath(r)
+		if !protected {
+			next.ServeHTTP(w, r)
+			return
+		}
+		if !ok {
+			writeJSONWithStatus(w, http.StatusUnauthorized, map[string]string{"error": "authentication required"})
+			return
+		}
+		if !auth.Allows(principal, required) {
+			writeJSONWithStatus(w, http.StatusForbidden, map[string]string{"error": "forbidden"})
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
+func (s *Server) authenticateRequest(r *http.Request) (auth.Principal, bool) {
+	if header := r.Header.Get("Authorization"); strings.HasPrefix(header, "Bearer ") {
+		principal, err := s.auth.ValidateBearerToken(r.Context(), strings.TrimSpace(strings.TrimPrefix(header, "Bearer ")))
+		if err == nil {
+			return principal, true
+		}
+		s.logger.Warn("invalid bearer token", "error", err)
+		return auth.Principal{}, false
+	}
+	cookie, err := r.Cookie(auth.SessionCookieName)
+	if err != nil || cookie.Value == "" {
+		return auth.Principal{}, false
+	}
+	principal, err := s.auth.ValidateSessionToken(r.Context(), cookie.Value)
+	if err != nil {
+		return auth.Principal{}, false
+	}
+	return principal, true
+}
+
+func requiredScopeForPath(r *http.Request) (auth.Scope, bool) {
+	path := r.URL.Path
+	method := r.Method
+	switch {
+	case strings.HasPrefix(path, "/api/auth/"):
+		if path == "/api/auth/me" || path == "/api/auth/logout" || path == "/api/auth/password/change" || path == "/api/auth/account" {
+			return auth.ScopeDocsRead, true
+		}
+		return "", false
+	case strings.HasPrefix(path, "/api/device/"):
+		if path == "/api/device/approve" || path == "/api/device/verify" {
+			return auth.ScopeDocsRead, true
+		}
+		return "", false
+	case strings.HasPrefix(path, "/api/tokens"):
+		return auth.ScopeDocsRead, true
+	case path == "/ws":
+		return auth.ScopeDocsRead, true
+	case strings.HasPrefix(path, "/api/admin/"):
+		return auth.ScopeAdmin, true
+	case strings.HasPrefix(path, "/api/documents/") && method != http.MethodGet:
+		return auth.ScopeDocsWrite, true
+	case strings.HasPrefix(path, "/api/uploads"):
+		return auth.ScopeDocsWrite, true
+	case strings.HasPrefix(path, "/api/sync/"):
+		if method == http.MethodPost {
+			return auth.ScopeSyncWrite, true
+		}
+		return auth.ScopeSyncRead, true
+	case strings.HasPrefix(path, "/api/content/"):
+		return auth.ScopeSyncRead, true
+	case strings.HasSuffix(path, "/edit"):
+		return auth.ScopeDocsWrite, true
+	default:
+		return "", false
+	}
+}
+
 type statusWriter struct {
 	http.ResponseWriter
 	status int