mirror of
https://github.com/caddyserver/caddy.git
synced 2026-11-11 19:37:55 +00:00
Kévin Dunglas
6cdffe9502
* requestbody: reject oversized Content-Length before the next handler When max_size is set and the request declares a Content-Length above it, respond 413 right away instead of letting the next handler start and fail mid-read. Bodies of unknown length are still limited by MaxBytesReader. Both paths return the same error, so handle_errors sees no difference. * caddytest: send unknown-length bodies in max_size placeholder tests request_body now answers 413 for a declared Content-Length over max_size before the placeholder reads the body, so these tests no longer covered the read path and the direct respond one failed. * requestbody: keep the body limited for error routes Error routes get the same request, so wrap the body before the early 413 to stop them from reading past max_size.
97 lines
3.0 KiB
Go
97 lines
3.0 KiB
Go
// Copyright 2015 Matthew Holt and The Caddy Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package requestbody
|
|
|
|
import (
|
|
"errors"
|
|
"io"
|
|
"net/http"
|
|
"strings"
|
|
|
|
"github.com/caddyserver/caddy/v2"
|
|
"github.com/caddyserver/caddy/v2/modules/caddyhttp"
|
|
)
|
|
|
|
func init() {
|
|
caddy.RegisterModule(RequestBody{})
|
|
}
|
|
|
|
// RequestBody is a middleware for manipulating the request body.
|
|
type RequestBody struct {
|
|
// The maximum number of bytes to allow reading from the body by a later handler.
|
|
// If more bytes are read, an error with HTTP status 413 is returned.
|
|
// Requests declaring a larger Content-Length get the same error
|
|
// before any later handler runs.
|
|
MaxSize int64 `json:"max_size,omitempty"`
|
|
|
|
// This field permit to replace body on the fly
|
|
// EXPERIMENTAL. Subject to change/removal.
|
|
Set string `json:"set,omitempty"`
|
|
}
|
|
|
|
// CaddyModule returns the Caddy module information.
|
|
func (RequestBody) CaddyModule() caddy.ModuleInfo {
|
|
return caddy.ModuleInfo{
|
|
ID: "http.handlers.request_body",
|
|
New: func() caddy.Module { return new(RequestBody) },
|
|
}
|
|
}
|
|
|
|
func (rb RequestBody) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
|
|
if rb.Set != "" {
|
|
if r.Body != nil {
|
|
err := r.Body.Close()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
|
|
// Only known placeholders are replaced: the body is user-supplied and
|
|
// often JSON, whose braces would otherwise be read as placeholders and
|
|
// blanked, sending an empty body instead. This matches the respond body.
|
|
replacedBody := repl.ReplaceKnown(rb.Set, "")
|
|
r.Body = io.NopCloser(strings.NewReader(replacedBody))
|
|
r.ContentLength = int64(len(replacedBody))
|
|
}
|
|
if r.Body == nil {
|
|
return next.ServeHTTP(w, r)
|
|
}
|
|
if rb.MaxSize > 0 {
|
|
// wrap before rejecting: error routes get this request and may read the body
|
|
r.Body = errorWrapper{http.MaxBytesReader(w, r.Body, rb.MaxSize)}
|
|
if r.ContentLength > rb.MaxSize {
|
|
return caddyhttp.Error(http.StatusRequestEntityTooLarge, &http.MaxBytesError{Limit: rb.MaxSize})
|
|
}
|
|
}
|
|
return next.ServeHTTP(w, r)
|
|
}
|
|
|
|
// errorWrapper wraps errors that are returned from Read()
|
|
// so that they can be associated with a proper status code.
|
|
type errorWrapper struct {
|
|
io.ReadCloser
|
|
}
|
|
|
|
func (ew errorWrapper) Read(p []byte) (n int, err error) {
|
|
n, err = ew.ReadCloser.Read(p)
|
|
if _, ok := errors.AsType[*http.MaxBytesError](err); ok {
|
|
err = caddyhttp.Error(http.StatusRequestEntityTooLarge, err)
|
|
}
|
|
return n, err
|
|
}
|
|
|
|
// Interface guard
|
|
var _ caddyhttp.MiddlewareHandler = (*RequestBody)(nil)
|