consolidate RequestInfo into MeekChannel with a simplified Negotiate method

This commit is contained in:
Serene Han 2016-01-19 18:06:40 -08:00
parent b4a07c4192
commit 5e9b23de9e
2 changed files with 37 additions and 52 deletions

View file

@ -1,5 +1,5 @@
// Exchange WebRTC SessionDescriptions over a domain-fronted HTTP
// signalling channel.
// signaling channel.
package main
import (
@ -12,71 +12,60 @@ import (
"github.com/keroserene/go-webrtc"
)
// RequestInfo encapsulates all the configuration used for a requestresponse
// roundtrip, including variables that may come from SOCKS args or from the
// command line.
type RequestInfo struct {
// What to put in the X-Session-ID header - SessionID string
// The desired potentially filtered URL to request.
URL *url.URL
// Meek Signalling Channel.
type MeekChannel struct {
// The Host header to put in the HTTP request (optional and may be
// different from the host name in URL).
Host string
Host string
Method string
trueURL *url.URL
externalUrl string
transport http.Transport // Used to make all requests.
}
func NewRequestInfo(targetUrl string, front string) *RequestInfo {
info := new(RequestInfo)
requestUrl, err := url.Parse(targetUrl)
// Construct a new MeekChannel, where
// |broker| is the URL of the facilitating program which assigns proxies
// to clients, and
// |front| is URL of the front domain.
func NewMeekChannel(broker string, front string) *MeekChannel {
targetUrl, err := url.Parse(broker)
if nil != err {
return nil
}
info.URL = requestUrl
info.Host = front
return info
}
mc := new(MeekChannel)
mc.Host = front
mc.Method = "POST"
// Meek Signalling Channel.
type MeekChannel struct {
info *RequestInfo
// Used to make all requests.
transport http.Transport
}
mc.trueURL = targetUrl
mc.externalUrl = front + "/reg/test" // TODO: Have a better suffix.
func NewMeekChannel(info *RequestInfo) *MeekChannel {
m := new(MeekChannel)
// We make a copy of DefaultTransport because we want the default Dial
// and TLSHandshakeTimeout settings. But we want to disable the default
// ProxyFromEnvironment setting. Proxy is overridden below if
// options.ProxyURL is set.
m.transport = *http.DefaultTransport.(*http.Transport)
m.transport.Proxy = nil
m.info = info
return m
// ProxyFromEnvironment setting.
mc.transport = *http.DefaultTransport.(*http.Transport)
mc.transport.Proxy = nil
return mc
}
// Do an HTTP roundtrip using the payload data in buf.
func (mc *MeekChannel) roundTripHTTP(buf []byte) (*http.Response, error) {
// Compose an innocent looking request.
req, err := http.NewRequest("POST", mc.info.Host+"/reg/123", bytes.NewReader(buf))
// Roundtrip HTTP POST using WebRTC SessionDescriptions.
//
// Sends an SDP offer to the meek broker, which assigns a proxy and responds
// with an SDP answer from a designated remote WebRTC peer.
func (mc *MeekChannel) Negotiate(offer *webrtc.SessionDescription) (
*webrtc.SessionDescription, error) {
data := bytes.NewReader([]byte(offer.Serialize()))
request, err := http.NewRequest(mc.Method, mc.externalUrl, data)
if nil != err {
return nil, err
}
// Set actually desired host in the request.
req.Host = mc.info.URL.String()
// req.Header.Set("X-Session-Id", m.info.SessionID)
return mc.transport.RoundTrip(req)
}
// Send an SDP offer to the meek facilitator, and wait for an SDP answer from
// the assigned proxy in the response.
func (mc *MeekChannel) Negotiate(offer *webrtc.SessionDescription) (
*webrtc.SessionDescription, error) {
resp, err := mc.roundTripHTTP([]byte(offer.Serialize()))
request.Host = mc.trueURL.String()
resp, err := mc.transport.RoundTrip(request)
if nil != err {
return nil, err
}
defer resp.Body.Close()
log.Println("MeekChannel Response: ", resp)
body, err := ioutil.ReadAll(resp.Body)
if nil != err {
return nil, err
@ -85,7 +74,6 @@ func (mc *MeekChannel) Negotiate(offer *webrtc.SessionDescription) (
return answer, nil
}
// Simple interim non-fronting HTTP POST negotiation, to be removed when more
// general fronting is present.
func sendOfferHTTP(url string, offer *webrtc.SessionDescription) (*webrtc.SessionDescription, error) {