126 lines
3.4 KiB
Go
126 lines
3.4 KiB
Go
// Copyright 2017 Google Inc.
|
|
//
|
|
// 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 tcpproxy
|
|
|
|
import (
|
|
"bufio"
|
|
"bytes"
|
|
"context"
|
|
"net/http"
|
|
)
|
|
|
|
// AddHTTPHostRoute appends a route to the ipPort listener that
|
|
// routes to dest if the incoming HTTP/1.x Host header name is
|
|
// httpHost. If it doesn't match, rule processing continues for any
|
|
// additional routes on ipPort.
|
|
//
|
|
// The ipPort is any valid net.Listen TCP address.
|
|
func (p *Proxy) AddHTTPHostRoute(ipPort, httpHost string, dest Target) {
|
|
p.AddHTTPHostMatchRoute(ipPort, equals(httpHost), dest)
|
|
}
|
|
|
|
// AddHTTPHostMatchRoute appends a route to the ipPort listener that
|
|
// routes to dest if the incoming HTTP/1.x Host header name is
|
|
// accepted by matcher. If it doesn't match, rule processing continues
|
|
// for any additional routes on ipPort.
|
|
//
|
|
// The ipPort is any valid net.Listen TCP address.
|
|
func (p *Proxy) AddHTTPHostMatchRoute(ipPort string, match Matcher, dest Target) {
|
|
p.addRoute(ipPort, httpHostMatch{match, dest})
|
|
}
|
|
|
|
type httpHostMatch struct {
|
|
matcher Matcher
|
|
target Target
|
|
}
|
|
|
|
func (m httpHostMatch) match(br *bufio.Reader) (Target, string) {
|
|
hh := httpHostHeader(br)
|
|
if m.matcher(context.TODO(), hh) {
|
|
return m.target, hh
|
|
}
|
|
return nil, ""
|
|
}
|
|
|
|
// httpHostHeader returns the HTTP Host header from br without
|
|
// consuming any of its bytes. It returns "" if it can't find one.
|
|
func httpHostHeader(br *bufio.Reader) string {
|
|
const maxPeek = 4 << 10
|
|
peekSize := 0
|
|
for {
|
|
peekSize++
|
|
if peekSize > maxPeek {
|
|
b, _ := br.Peek(br.Buffered())
|
|
return httpHostHeaderFromBytes(b)
|
|
}
|
|
b, err := br.Peek(peekSize)
|
|
if n := br.Buffered(); n > peekSize {
|
|
b, _ = br.Peek(n)
|
|
peekSize = n
|
|
}
|
|
if len(b) > 0 {
|
|
if b[0] < 'A' || b[0] > 'Z' {
|
|
// Doesn't look like an HTTP verb
|
|
// (GET, POST, etc).
|
|
return ""
|
|
}
|
|
if bytes.Index(b, crlfcrlf) != -1 || bytes.Index(b, lflf) != -1 {
|
|
req, err := http.ReadRequest(bufio.NewReader(bytes.NewReader(b)))
|
|
if err != nil {
|
|
return ""
|
|
}
|
|
if len(req.Header["Host"]) > 1 {
|
|
// TODO(bradfitz): what does
|
|
// ReadRequest do if there are
|
|
// multiple Host headers?
|
|
return ""
|
|
}
|
|
return req.Host
|
|
}
|
|
}
|
|
if err != nil {
|
|
return httpHostHeaderFromBytes(b)
|
|
}
|
|
}
|
|
}
|
|
|
|
var (
|
|
lfHostColon = []byte("\nHost:")
|
|
lfhostColon = []byte("\nhost:")
|
|
crlf = []byte("\r\n")
|
|
lf = []byte("\n")
|
|
crlfcrlf = []byte("\r\n\r\n")
|
|
lflf = []byte("\n\n")
|
|
)
|
|
|
|
func httpHostHeaderFromBytes(b []byte) string {
|
|
if i := bytes.Index(b, lfHostColon); i != -1 {
|
|
return string(bytes.TrimSpace(untilEOL(b[i+len(lfHostColon):])))
|
|
}
|
|
if i := bytes.Index(b, lfhostColon); i != -1 {
|
|
return string(bytes.TrimSpace(untilEOL(b[i+len(lfhostColon):])))
|
|
}
|
|
return ""
|
|
}
|
|
|
|
// untilEOL returns v, truncated before the first '\n' byte, if any.
|
|
// The returned slice may include a '\r' at the end.
|
|
func untilEOL(v []byte) []byte {
|
|
if i := bytes.IndexByte(v, '\n'); i != -1 {
|
|
return v[:i]
|
|
}
|
|
return v
|
|
}
|