Secure functionality implementation
package main
import (
"github.com/gin-gonic/gin"
"net/http"
)
func main() {
r := gin.Default()
r.DELETE("/user/:id", deleteUser)
r.Run()
}
func deleteUser(c *gin.Context) {
id := c.Param("id")
// Assume we have a function deleteUserFromDatabase(id string) that deletes a user from the database
deleteUserFromDatabase(id)
c.String(http.StatusOK, "User deleted")
}
The above code represents an insecure functionality vulnerability because it allows anyone to delete a user from the system. The DELETE endpoint
/user/:id is open to all clients without any form of authentication or authorization. This means that an attacker can send a DELETE request to this endpoint with any user ID to delete the user associated with that ID.
The
deleteUser function retrieves the user ID from the URL parameters and passes it to the
deleteUserFromDatabase function (which is assumed to exist in this example). This function deletes the user from the database. After the user is deleted, a 200 OK response with the message "User deleted" is sent back to the client.
This is a serious vulnerability because it allows anyone to delete users from the system, potentially leading to data loss and unauthorized access to the system.
package main
import (
"github.com/gin-gonic/gin"
"net/http"
"github.com/dgrijalva/jwt-go"
"time"
)
var SECRET_KEY = []byte("mySecretKey")
func main() {
r := gin.Default()
r.Use(AuthMiddleware())
r.DELETE("/user/:id", deleteUser)
r.Run()
}
func deleteUser(c *gin.Context) {
id := c.Param("id")
// Validate the id
if id == "" {
c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid user ID"})
return
}
// Assume we have a function deleteUserFromDatabase(id string) that deletes a user from the database
deleteUserFromDatabase(id)
c.String(http.StatusOK, "User deleted")
}
func AuthMiddleware() gin.HandlerFunc {
return func(c *gin.Context) {
tokenString := c.GetHeader("Authorization")
token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
return SECRET_KEY, nil
})
if err != nil {
c.JSON(http.StatusUnauthorized, "unauthorized")
c.Abort()
return
}
if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
c.Set("userId", claims["userId"])
} else {
c.JSON(http.StatusUnauthorized, "unauthorized")
c.Abort()
return
}
c.Next()
}
}
The updated code includes an authentication middleware that uses JWT (JSON Web Tokens) for user authentication. The middleware function
AuthMiddleware is used to authenticate the user before the
deleteUser function is called.
The
deleteUser function now also validates the user ID before proceeding with the deletion. If the ID is not valid, it returns a 400 Bad Request status code with an error message.
The
AuthMiddleware function retrieves the token from the
Authorization header of the request. It then parses and validates the token using the secret key. If the token is valid, it sets the user ID in the context and proceeds to the next handler. If the token is not valid, it returns a 401 Unauthorized status code and aborts the request.
This way, only authenticated users can access the
deleteUser functionality, and the user input is validated to prevent any malicious input that could lead to unauthorized deletion of users.
Please note that this is a basic implementation of JWT authentication and you may need to adjust it according to your needs. For example, you might want to store the secret key in a more secure way, handle token expiration, or add more claims to the token.
Also, remember to implement rate limiting or throttling mechanisms to prevent abuse of the
deleteUser functionality, consider implementing a soft delete mechanism instead of directly deleting the user from the database, regularly update and patch the dependencies used in the application, and perform regular security assessments and penetration testing.