From 898494118c41f341a994e1162b04c8f5a9b557b3 Mon Sep 17 00:00:00 2001
From: Henry <2671230065@qq.com>
Date: Sat, 3 Aug 2024 17:36:22 +0800
Subject: [PATCH] feat: invalidate token on logout

---
 server/common/auth.go  | 23 +++++++++++++++++++++++
 server/handles/auth.go |  9 +++++++++
 server/router.go       |  1 +
 3 files changed, 33 insertions(+)

diff --git a/server/common/auth.go b/server/common/auth.go
index b6a79b752aa..0de718cf9e8 100644
--- a/server/common/auth.go
+++ b/server/common/auth.go
@@ -3,6 +3,7 @@ package common
 import (
 	"time"
 
+	"github.com/Xhofe/go-cache"
 	"github.com/alist-org/alist/v3/internal/conf"
 	"github.com/alist-org/alist/v3/internal/model"
 	"github.com/golang-jwt/jwt/v4"
@@ -17,6 +18,8 @@ type UserClaims struct {
 	jwt.RegisteredClaims
 }
 
+var validTokenCache = cache.NewMemCache[bool]()
+
 func GenerateToken(user *model.User) (tokenString string, err error) {
 	claim := UserClaims{
 		Username: user.Username,
@@ -28,6 +31,10 @@ func GenerateToken(user *model.User) (tokenString string, err error) {
 		}}
 	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claim)
 	tokenString, err = token.SignedString(SecretKey)
+	if err != nil {
+		return "", err
+	}
+	validTokenCache.Set(tokenString, true)
 	return tokenString, err
 }
 
@@ -35,6 +42,9 @@ func ParseToken(tokenString string) (*UserClaims, error) {
 	token, err := jwt.ParseWithClaims(tokenString, &UserClaims{}, func(token *jwt.Token) (interface{}, error) {
 		return SecretKey, nil
 	})
+	if IsTokenInvalidated(tokenString) {
+		return nil, errors.New("token is invalidated")
+	}
 	if err != nil {
 		if ve, ok := err.(*jwt.ValidationError); ok {
 			if ve.Errors&jwt.ValidationErrorMalformed != 0 {
@@ -53,3 +63,16 @@ func ParseToken(tokenString string) (*UserClaims, error) {
 	}
 	return nil, errors.New("couldn't handle this token")
 }
+
+func InvalidateToken(tokenString string) error {
+	if tokenString == "" {
+		return nil // don't invalidate empty guest token
+	}
+	validTokenCache.Del(tokenString)
+	return nil
+}
+
+func IsTokenInvalidated(tokenString string) bool {
+	_, ok := validTokenCache.Get(tokenString)
+	return !ok
+}
diff --git a/server/handles/auth.go b/server/handles/auth.go
index 209bdd3a2b8..e1f512c4dc1 100644
--- a/server/handles/auth.go
+++ b/server/handles/auth.go
@@ -181,3 +181,12 @@ func Verify2FA(c *gin.Context) {
 		common.SuccessResp(c)
 	}
 }
+
+func LogOut(c *gin.Context) {
+	err := common.InvalidateToken(c.GetHeader("Authorization"))
+	if err != nil {
+		common.ErrorResp(c, err, 500)
+	} else {
+		common.SuccessResp(c)
+	}
+}
diff --git a/server/router.go b/server/router.go
index 5f784aa4b7d..5be593f7497 100644
--- a/server/router.go
+++ b/server/router.go
@@ -54,6 +54,7 @@ func Init(e *gin.Engine) {
 	auth.POST("/me/update", handles.UpdateCurrent)
 	auth.POST("/auth/2fa/generate", handles.Generate2FA)
 	auth.POST("/auth/2fa/verify", handles.Verify2FA)
+	auth.GET("/auth/logout", handles.LogOut)
 
 	// auth
 	api.GET("/auth/sso", handles.SSOLoginRedirect)