V2 alpha - initial version (#172)

Initial alpha codebase for version 2 of WireGuard Portal.
This version is considered unstable and incomplete (for example, no public REST API)! 
Use with care!


Fixes/Implements the following issues:
 - OAuth support #154, #1 
 - New Web UI with internationalisation support #98, #107, #89, #62
 - Postgres Support #49 
 - Improved Email handling #47, #119 
 - DNS Search Domain support #46 
 - Bugfixes #94, #48 

---------

Co-authored-by: Fabian Wechselberger <wechselbergerf@hotmail.com>

internal/app/api/v0/handlers/middleware_authentication.go

@@ -0,0 +1,85 @@
+package handlers
+
+import (
+	"github.com/gin-gonic/gin"
+	"github.com/h44z/wg-portal/internal/app"
+	"github.com/h44z/wg-portal/internal/app/api/v0/model"
+	"github.com/h44z/wg-portal/internal/domain"
+	"net/http"
+)
+
+type Scope string
+
+const (
+	ScopeAdmin   Scope = "ADMIN" // Admin scope contains all other scopes
+	ScopeSwagger Scope = "SWAGGER"
+	ScopeUser    Scope = "USER"
+)
+
+type authenticationHandler struct {
+	app     *app.App
+	Session SessionStore
+}
+
+// LoggedIn checks if a user is logged in. If scopes are given, they are validated as well.
+func (h authenticationHandler) LoggedIn(scopes ...Scope) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		session := h.Session.GetData(c)
+
+		if !session.LoggedIn {
+			// Abort the request with the appropriate error code
+			c.Abort()
+			c.JSON(http.StatusUnauthorized, model.Error{Code: http.StatusUnauthorized, Message: "not logged in"})
+			return
+		}
+
+		if !UserHasScopes(session, scopes...) {
+			// Abort the request with the appropriate error code
+			c.Abort()
+			c.JSON(http.StatusForbidden, model.Error{Code: http.StatusForbidden, Message: "not enough permissions"})
+			return
+		}
+
+		// Check if logged-in user is still valid
+		if !h.app.Authenticator.IsUserValid(c.Request.Context(), domain.UserIdentifier(session.UserIdentifier)) {
+			h.Session.DestroyData(c)
+			c.Abort()
+			c.JSON(http.StatusUnauthorized, model.Error{Code: http.StatusUnauthorized, Message: "session no longer available"})
+			return
+		}
+
+		c.Set(domain.CtxUserInfo, &domain.ContextUserInfo{
+			Id:      domain.UserIdentifier(session.UserIdentifier),
+			IsAdmin: session.IsAdmin,
+		})
+
+		// Continue down the chain to handler etc
+		c.Next()
+	}
+}
+
+func UserHasScopes(session SessionData, scopes ...Scope) bool {
+	// No scopes give, so the check should succeed
+	if len(scopes) == 0 {
+		return true
+	}
+
+	// check if user has admin scope
+	if session.IsAdmin {
+		return true
+	}
+
+	// Check if admin scope is required
+	for _, scope := range scopes {
+		if scope == ScopeAdmin {
+			return false
+		}
+	}
+
+	// For all other scopes, a logged-in user is sufficient (for now)
+	if session.LoggedIn {
+		return true
+	}
+
+	return false
+}