commit 827972e2bfebdfb0555228f69de48711a7e5f1b1 Author: David Fifield david@bamsoftware.com Date: Sat Jul 15 12:04:59 2017 -0700

Customize reflect.go for Snowflake broker.

Don't need Meek-IP. --- appengine/README | 18 +++++++----------- appengine/app.yaml | 3 --- appengine/reflect.go | 31 ++++++------------------------- 3 files changed, 13 insertions(+), 39 deletions(-)

diff --git a/appengine/README b/appengine/README index d71277a..bec9fcb 100644 --- a/appengine/README +++ b/appengine/README @@ -1,7 +1,5 @@ -This component runs on Google App Engine. It lies between meek-client -and meek-server. The App Engine component receives requests from the -client and forwards them to the server, then receives responses from the -server and forwards them to the client. +This component runs on Google App Engine. It reflects domain-fronted +requests from a client to the Snowflake broker.

You need the Go App Engine SDK in order to deploy the app. https://cloud.google.com/sdk/docs/#linux @@ -10,8 +8,7 @@ After unpacking, install the app-engine-go component:

To test locally, run google-cloud-sdk/bin/dev_appserver.py app.yaml -The app will be running at http://127.0.0.1:8080/. You can test broker -forwarding function by browsing to http://127.0.0.1:8000/ip. +The app will be running at http://127.0.0.1:8080/.

To deploy to App Engine, first create a new project and app. You have to think of a unique name (marked as "<appname>" in the commands). You only @@ -23,9 +20,8 @@ log in to a Google account. Then to deploy the project, run: google-cloud-sdk/bin/gcloud app deploy --project=<appname>

-To configure meek-client to talk to the App Engine app, provide -"https://<appname>.appspot.com/" as the url and "www.google.com" as the -front domain. +To configure the Snowflake client to talk to the App Engine app, provide +"https://<appname>.appspot.com/" as the --url option. UseBridges 1 - Bridge meek 0.0.2.0:1 url=https://example.appspot.com/ front=www.google.com - ClientTransportPlugin meek exec ./meek-client --log meek-client.log + Bridge snowflake 0.0.2.0:1 + ClientTransportPlugin snowflake exec ./client -url https://<appname>.appspot.com/ -front www.google.com diff --git a/appengine/app.yaml b/appengine/app.yaml index ff6efc1..44df436 100644 --- a/appengine/app.yaml +++ b/appengine/app.yaml @@ -1,8 +1,5 @@ runtime: go api_version: go1 -automatic_scaling: - max_idle_instances: 2 - min_pending_latency: 1000ms

handlers: - url: /.* diff --git a/appengine/reflect.go b/appengine/reflect.go index ccf11f3..f6b5336 100644 --- a/appengine/reflect.go +++ b/appengine/reflect.go @@ -1,10 +1,9 @@ -// A web app for Google App Engine that proxies HTTP requests and responses to a -// Tor relay running meek-server. +// A web app for Google App Engine that proxies HTTP requests and responses to +// the Snowflake broker. package reflect

import ( "io" - "net" "net/http" "net/url" "time" @@ -14,7 +13,7 @@ import ( )

const ( - forwardURL = "https://meek.bamsoftware.com/" + forwardURL = "https://snowflake-broker.bamsoftware.com/" // A timeout of 0 means to use the App Engine default (5 seconds). urlFetchTimeout = 20 * time.Second ) @@ -32,26 +31,14 @@ func pathJoin(a, b string) string { return a + b }

-// We reflect only a whitelisted set of header fields. In requests, the full -// list includes things like User-Agent and X-Appengine-Country that the Tor -// bridge doesn't need to know. In responses, there may be things like -// Transfer-Encoding that interfere with App Engine's own hop-by-hop headers. +// We reflect only a whitelisted set of header fields. Otherwise, we may copy +// headers like Transfer-Encoding that interfere with App Engine's own +// hop-by-hop headers. var reflectedHeaderFields = []string{ "Content-Type", "X-Session-Id", }

-// Get the original client IP address as a string. When using the standard -// net/http server, Request.RemoteAddr is a "host:port" string; however App -// Engine seems to use just "host". We check for both to be safe. -func getClientAddr(r *http.Request) string { - host, _, err := net.SplitHostPort(r.RemoteAddr) - if err == nil { - return host - } - return r.RemoteAddr -} - // Make a copy of r, with the URL being changed to be relative to forwardURL, // and including only the headers in reflectedHeaderFields. func copyRequest(r *http.Request) (*http.Request, error) { @@ -74,12 +61,6 @@ func copyRequest(r *http.Request) (*http.Request, error) { } } } - // Set the original client IP address in a Meek-IP header. We would use - // X-Forwarded-For, but App Engine prohibits setting that header: - // https://cloud.google.com/appengine/docs/standard/go/outbound-requests#reques... - // We could use Forwarded from RFC 7239, but other CDNs already use - // X-Forwarded-For and this way we only need one parser. - c.Header.Add("Meek-IP", getClientAddr(r)) return c, nil }