portainer/api/http/csrf/csrf.go

110 lines
2.9 KiB
Go

package csrf
import (
"crypto/rand"
"errors"
"fmt"
"net/http"
"os"
"github.com/portainer/portainer/api/http/security"
httperror "github.com/portainer/portainer/pkg/libhttp/error"
gcsrf "github.com/gorilla/csrf"
"github.com/rs/zerolog/log"
"github.com/urfave/negroni"
)
const csrfSkipHeader = "X-CSRF-Token-Skip"
func SkipCSRFToken(w http.ResponseWriter) {
w.Header().Set(csrfSkipHeader, "1")
}
func WithProtect(handler http.Handler, trustedOrigins []string) (http.Handler, error) {
// IsDockerDesktopExtension is used to check if we should skip csrf checks in the request bouncer (ShouldSkipCSRFCheck)
// DOCKER_EXTENSION is set to '1' in build/docker-extension/docker-compose.yml
isDockerDesktopExtension := false
if val, ok := os.LookupEnv("DOCKER_EXTENSION"); ok && val == "1" {
isDockerDesktopExtension = true
}
handler = withSendCSRFToken(handler)
token := make([]byte, 32)
if _, err := rand.Read(token); err != nil {
return nil, fmt.Errorf("failed to generate CSRF token: %w", err)
}
handler = gcsrf.Protect(
token,
gcsrf.Path("/"),
gcsrf.Secure(false),
gcsrf.TrustedOrigins(trustedOrigins),
gcsrf.ErrorHandler(withErrorHandler(trustedOrigins)),
)(handler)
return withSkipCSRF(handler, isDockerDesktopExtension), nil
}
func withSendCSRFToken(handler http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
sw := negroni.NewResponseWriter(w)
sw.Before(func(sw negroni.ResponseWriter) {
if len(sw.Header().Get(csrfSkipHeader)) > 0 {
sw.Header().Del(csrfSkipHeader)
return
}
if statusCode := sw.Status(); statusCode >= 200 && statusCode < 300 {
sw.Header().Set("X-CSRF-Token", gcsrf.Token(r))
}
})
handler.ServeHTTP(sw, r)
})
}
func withSkipCSRF(handler http.Handler, isDockerDesktopExtension bool) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
skip, err := security.ShouldSkipCSRFCheck(r, isDockerDesktopExtension)
if err != nil {
httperror.WriteError(w, http.StatusForbidden, err.Error(), err)
return
}
if skip {
r = gcsrf.UnsafeSkipCheck(r)
}
handler.ServeHTTP(w, r)
})
}
func withErrorHandler(trustedOrigins []string) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
err := gcsrf.FailureReason(r)
if errors.Is(err, gcsrf.ErrBadOrigin) || errors.Is(err, gcsrf.ErrBadReferer) || errors.Is(err, gcsrf.ErrNoReferer) {
log.Error().Err(err).
Str("request_url", r.URL.String()).
Str("host", r.Host).
Str("x_forwarded_proto", r.Header.Get("X-Forwarded-Proto")).
Str("forwarded", r.Header.Get("Forwarded")).
Str("origin", r.Header.Get("Origin")).
Str("referer", r.Header.Get("Referer")).
Strs("trusted_origins", trustedOrigins).
Msg("Failed to validate Origin or Referer")
}
http.Error(
w,
http.StatusText(http.StatusForbidden)+" - "+err.Error(),
http.StatusForbidden,
)
})
}