Session improvements (#510)

handler/routes.go

@@ -93,32 +93,41 @@ func Login(db store.IStore) echo.HandlerFunc {
 		}
 
 		if userCorrect && passwordCorrect {
-			// TODO: refresh the token
 			ageMax := 0
-			expiration := time.Now().Add(24 * time.Hour)
 			if rememberMe {
-				ageMax = 86400
-				expiration.Add(144 * time.Hour)
+				ageMax = 86400 * 7
 			}
+
+			cookiePath := util.GetCookiePath()
+
 			sess, _ := session.Get("session", c)
 			sess.Options = &sessions.Options{
-				Path:     util.BasePath,
+				Path:     cookiePath,
 				MaxAge:   ageMax,
 				HttpOnly: true,
+				SameSite: http.SameSiteLaxMode,
 			}
 
 			// set session_token
 			tokenUID := xid.New().String()
+			now := time.Now().UTC().Unix()
 			sess.Values["username"] = dbuser.Username
+			sess.Values["user_hash"] = util.GetDBUserCRC32(dbuser)
 			sess.Values["admin"] = dbuser.Admin
 			sess.Values["session_token"] = tokenUID
+			sess.Values["max_age"] = ageMax
+			sess.Values["created_at"] = now
+			sess.Values["updated_at"] = now
 			sess.Save(c.Request(), c.Response())
 
 			// set session_token in cookie
 			cookie := new(http.Cookie)
 			cookie.Name = "session_token"
+			cookie.Path = cookiePath
 			cookie.Value = tokenUID
-			cookie.Expires = expiration
+			cookie.MaxAge = ageMax
+			cookie.HttpOnly = true
+			cookie.SameSite = http.SameSiteLaxMode
 			c.SetCookie(cookie)
 
 			return c.JSON(http.StatusOK, jsonHTTPResponse{true, "Logged in successfully"})
@@ -256,7 +265,7 @@ func UpdateUser(db store.IStore) echo.HandlerFunc {
 		log.Infof("Updated user information successfully")
 
 		if previousUsername == currentUser(c) {
-			setUser(c, user.Username, user.Admin)
+			setUser(c, user.Username, user.Admin, util.GetDBUserCRC32(user))
 		}
 
 		return c.JSON(http.StatusOK, jsonHTTPResponse{true, "Updated user information successfully"})

handler/session.go

@@ -3,7 +3,9 @@ package handler
 import (
 	"fmt"
 	"net/http"
+	"time"
 
+	"github.com/gorilla/sessions"
 	"github.com/labstack/echo-contrib/session"
 	"github.com/labstack/echo/v4"
 	"github.com/ngoduykhanh/wireguard-ui/util"
@@ -23,6 +25,15 @@ func ValidSession(next echo.HandlerFunc) echo.HandlerFunc {
 	}
 }
 
+// RefreshSession must only be used after ValidSession middleware
+// RefreshSession checks if the session is eligible for the refresh, but doesn't check if it's fully valid
+func RefreshSession(next echo.HandlerFunc) echo.HandlerFunc {
+	return func(c echo.Context) error {
+		doRefreshSession(c)
+		return next(c)
+	}
+}
+
 func NeedsAdmin(next echo.HandlerFunc) echo.HandlerFunc {
 	return func(c echo.Context) error {
 		if !isAdmin(c) {
@@ -41,9 +52,146 @@ func isValidSession(c echo.Context) bool {
 	if err != nil || sess.Values["session_token"] != cookie.Value {
 		return false
 	}
+
+	// Check time bounds
+	createdAt := getCreatedAt(sess)
+	updatedAt := getUpdatedAt(sess)
+	maxAge := getMaxAge(sess)
+	// Temporary session is considered valid within 24h if browser is not closed before
+	// This value is not saved and is used as virtual expiration
+	if maxAge == 0 {
+		maxAge = 86400
+	}
+	expiration := updatedAt + int64(maxAge)
+	now := time.Now().UTC().Unix()
+	if updatedAt > now || expiration < now || createdAt+util.SessionMaxDuration < now {
+		return false
+	}
+
+	// Check if user still exists and unchanged
+	username := fmt.Sprintf("%s", sess.Values["username"])
+	userHash := getUserHash(sess)
+	if uHash, ok := util.DBUsersToCRC32[username]; !ok || userHash != uHash {
+		return false
+	}
+
 	return true
 }
 
+// Refreshes a "remember me" session when the user visits web pages (not API)
+// Session must be valid before calling this function
+// Refresh is performed at most once per 24h
+func doRefreshSession(c echo.Context) {
+	if util.DisableLogin {
+		return
+	}
+
+	sess, _ := session.Get("session", c)
+	maxAge := getMaxAge(sess)
+	if maxAge <= 0 {
+		return
+	}
+
+	oldCookie, err := c.Cookie("session_token")
+	if err != nil || sess.Values["session_token"] != oldCookie.Value {
+		return
+	}
+
+	// Refresh no sooner than 24h
+	createdAt := getCreatedAt(sess)
+	updatedAt := getUpdatedAt(sess)
+	expiration := updatedAt + int64(getMaxAge(sess))
+	now := time.Now().UTC().Unix()
+	if updatedAt > now || expiration < now || now-updatedAt < 86_400 || createdAt+util.SessionMaxDuration < now {
+		return
+	}
+
+	cookiePath := util.GetCookiePath()
+
+	sess.Values["updated_at"] = now
+	sess.Options = &sessions.Options{
+		Path:     cookiePath,
+		MaxAge:   maxAge,
+		HttpOnly: true,
+		SameSite: http.SameSiteLaxMode,
+	}
+	sess.Save(c.Request(), c.Response())
+
+	cookie := new(http.Cookie)
+	cookie.Name = "session_token"
+	cookie.Path = cookiePath
+	cookie.Value = oldCookie.Value
+	cookie.MaxAge = maxAge
+	cookie.HttpOnly = true
+	cookie.SameSite = http.SameSiteLaxMode
+	c.SetCookie(cookie)
+}
+
+// Get time in seconds this session is valid without updating
+func getMaxAge(sess *sessions.Session) int {
+	if util.DisableLogin {
+		return 0
+	}
+
+	maxAge := sess.Values["max_age"]
+
+	switch typedMaxAge := maxAge.(type) {
+	case int:
+		return typedMaxAge
+	default:
+		return 0
+	}
+}
+
+// Get a timestamp in seconds of the time the session was created
+func getCreatedAt(sess *sessions.Session) int64 {
+	if util.DisableLogin {
+		return 0
+	}
+
+	createdAt := sess.Values["created_at"]
+
+	switch typedCreatedAt := createdAt.(type) {
+	case int64:
+		return typedCreatedAt
+	default:
+		return 0
+	}
+}
+
+// Get a timestamp in seconds of the last session update
+func getUpdatedAt(sess *sessions.Session) int64 {
+	if util.DisableLogin {
+		return 0
+	}
+
+	lastUpdate := sess.Values["updated_at"]
+
+	switch typedLastUpdate := lastUpdate.(type) {
+	case int64:
+		return typedLastUpdate
+	default:
+		return 0
+	}
+}
+
+// Get CRC32 of a user at the moment of log in
+// Any changes to user will result in logout of other (not updated) sessions
+func getUserHash(sess *sessions.Session) uint32 {
+	if util.DisableLogin {
+		return 0
+	}
+
+	userHash := sess.Values["user_hash"]
+
+	switch typedUserHash := userHash.(type) {
+	case uint32:
+		return typedUserHash
+	default:
+		return 0
+	}
+}
+
 // currentUser to get username of logged in user
 func currentUser(c echo.Context) string {
 	if util.DisableLogin {
@@ -66,9 +214,10 @@ func isAdmin(c echo.Context) bool {
 	return admin == "true"
 }
 
-func setUser(c echo.Context, username string, admin bool) {
+func setUser(c echo.Context, username string, admin bool, userCRC32 uint32) {
 	sess, _ := session.Get("session", c)
 	sess.Values["username"] = username
+	sess.Values["user_hash"] = userCRC32
 	sess.Values["admin"] = admin
 	sess.Save(c.Request(), c.Response())
 }
@@ -77,7 +226,24 @@ func setUser(c echo.Context, username string, admin bool) {
 func clearSession(c echo.Context) {
 	sess, _ := session.Get("session", c)
 	sess.Values["username"] = ""
+	sess.Values["user_hash"] = 0
 	sess.Values["admin"] = false
 	sess.Values["session_token"] = ""
+	sess.Values["max_age"] = -1
+	sess.Options.MaxAge = -1
 	sess.Save(c.Request(), c.Response())
+
+	cookiePath := util.GetCookiePath()
+
+	cookie, err := c.Cookie("session_token")
+	if err != nil {
+		cookie = new(http.Cookie)
+	}
+
+	cookie.Name = "session_token"
+	cookie.Path = cookiePath
+	cookie.MaxAge = -1
+	cookie.HttpOnly = true
+	cookie.SameSite = http.SameSiteLaxMode
+	c.SetCookie(cookie)
 }