mirror of
				https://github.com/caddyserver/caddy.git
				synced 2025-10-31 10:37:24 -04:00 
			
		
		
		
	I am not a lawyer, but according to the appendix of the license, these boilerplate notices should be included with every source file.
		
			
				
	
	
		
			105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // Copyright 2015 Light Code Labs, LLC
 | |
| //
 | |
| // 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 limits
 | |
| 
 | |
| import (
 | |
| 	"io"
 | |
| 	"net/http"
 | |
| 
 | |
| 	"github.com/mholt/caddy/caddyhttp/httpserver"
 | |
| )
 | |
| 
 | |
| // Limit is a middleware to control request body size
 | |
| type Limit struct {
 | |
| 	Next       httpserver.Handler
 | |
| 	BodyLimits []httpserver.PathLimit
 | |
| }
 | |
| 
 | |
| func (l Limit) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
 | |
| 	if r.Body == nil {
 | |
| 		return l.Next.ServeHTTP(w, r)
 | |
| 	}
 | |
| 
 | |
| 	// apply the path-based request body size limit.
 | |
| 	for _, bl := range l.BodyLimits {
 | |
| 		if httpserver.Path(r.URL.Path).Matches(bl.Path) {
 | |
| 			r.Body = MaxBytesReader(w, r.Body, bl.Limit)
 | |
| 			break
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	return l.Next.ServeHTTP(w, r)
 | |
| }
 | |
| 
 | |
| // MaxBytesReader and its associated methods are borrowed from the
 | |
| // Go Standard library (comments intact). The only difference is that
 | |
| // it returns a ErrMaxBytesExceeded error instead of a generic error message
 | |
| // when the request body has exceeded the requested limit
 | |
| func MaxBytesReader(w http.ResponseWriter, r io.ReadCloser, n int64) io.ReadCloser {
 | |
| 	return &maxBytesReader{w: w, r: r, n: n}
 | |
| }
 | |
| 
 | |
| type maxBytesReader struct {
 | |
| 	w   http.ResponseWriter
 | |
| 	r   io.ReadCloser // underlying reader
 | |
| 	n   int64         // max bytes remaining
 | |
| 	err error         // sticky error
 | |
| }
 | |
| 
 | |
| func (l *maxBytesReader) Read(p []byte) (n int, err error) {
 | |
| 	if l.err != nil {
 | |
| 		return 0, l.err
 | |
| 	}
 | |
| 	if len(p) == 0 {
 | |
| 		return 0, nil
 | |
| 	}
 | |
| 	// If they asked for a 32KB byte read but only 5 bytes are
 | |
| 	// remaining, no need to read 32KB. 6 bytes will answer the
 | |
| 	// question of the whether we hit the limit or go past it.
 | |
| 	if int64(len(p)) > l.n+1 {
 | |
| 		p = p[:l.n+1]
 | |
| 	}
 | |
| 	n, err = l.r.Read(p)
 | |
| 
 | |
| 	if int64(n) <= l.n {
 | |
| 		l.n -= int64(n)
 | |
| 		l.err = err
 | |
| 		return n, err
 | |
| 	}
 | |
| 
 | |
| 	n = int(l.n)
 | |
| 	l.n = 0
 | |
| 
 | |
| 	// The server code and client code both use
 | |
| 	// maxBytesReader. This "requestTooLarge" check is
 | |
| 	// only used by the server code. To prevent binaries
 | |
| 	// which only using the HTTP Client code (such as
 | |
| 	// cmd/go) from also linking in the HTTP server, don't
 | |
| 	// use a static type assertion to the server
 | |
| 	// "*response" type. Check this interface instead:
 | |
| 	type requestTooLarger interface {
 | |
| 		requestTooLarge()
 | |
| 	}
 | |
| 	if res, ok := l.w.(requestTooLarger); ok {
 | |
| 		res.requestTooLarge()
 | |
| 	}
 | |
| 	l.err = httpserver.ErrMaxBytesExceeded
 | |
| 	return n, l.err
 | |
| }
 | |
| 
 | |
| func (l *maxBytesReader) Close() error {
 | |
| 	return l.r.Close()
 | |
| }
 |