Files
spend-sparrow/handler/middleware/cross_site_request_forgery.go

64 lines
1.5 KiB
Go

package middleware
import (
"fmt"
"me-fit/service"
"strings"
"net/http"
)
type csrfResponseWriter struct {
http.ResponseWriter
auth service.Auth
session *service.Session
}
func newCsrfResponseWriter(w http.ResponseWriter, auth service.Auth, session *service.Session) *csrfResponseWriter {
return &csrfResponseWriter{
ResponseWriter: w,
auth: auth,
session: session,
}
}
TODO: Create session for CSRF token
func (rr *csrfResponseWriter) Write(data []byte) (int, error) {
dataStr := string(data)
if strings.Contains(dataStr, "</form>") {
csrfToken, err := rr.auth.GetCsrfToken(rr.session)
if err == nil {
csrfField := fmt.Sprintf(`<input type="hidden" name="csrf-token" value="%s">`, csrfToken)
dataStr = strings.ReplaceAll(dataStr, "</form>", csrfField+"</form>")
}
}
return rr.ResponseWriter.Write([]byte(dataStr))
}
func CrossSiteRequestForgery(auth service.Auth) func(http.Handler) http.Handler {
return func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
session := GetSession(r)
if r.Method == http.MethodPost ||
r.Method == http.MethodPut ||
r.Method == http.MethodDelete ||
r.Method == http.MethodPatch {
csrfToken := r.FormValue("csrf-token")
if csrfToken == "" || !auth.IsCsrfTokenValid(csrfToken, session.Id) {
http.Error(w, "", http.StatusForbidden)
return
}
}
responseWriter := newCsrfResponseWriter(w, auth, session)
next.ServeHTTP(responseWriter, r)
})
}
}