From 4d70d8065e35e28ff397e17ae1c9abfb0883b61f Mon Sep 17 00:00:00 2001
From: Alex Kocharin <alex@kocharin.ru>
Date: Mon, 9 Dec 2013 07:58:25 +0400
Subject: [PATCH] add via tag to prevent loops

---
 lib/index.js         |  2 +-
 lib/local-storage.js |  4 +++-
 lib/storage.js       | 12 +++++++-----
 lib/up-storage.js    | 46 +++++++++++++++++++++++++++++++++++---------
 4 files changed, 48 insertions(+), 16 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index b89443ba6..0bc63fd24 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -101,7 +101,7 @@ module.exports = function(config_hash) {
 
 	// TODO: anonymous user?
 	app.get('/:package/:version?', can('access'), function(req, res, next) {
-		storage.get_package(req.params.package, function(err, info) {
+		storage.get_package(req.params.package, {req: req}, function(err, info) {
 			if (err) return next(err)
 			info = utils.filter_tarball_urls(info, req, config)
 
diff --git a/lib/local-storage.js b/lib/local-storage.js
index 1f3be6bd9..08b5955cb 100644
--- a/lib/local-storage.js
+++ b/lib/local-storage.js
@@ -371,7 +371,9 @@ Storage.prototype.get_tarball = function(name, filename, callback) {
 	return stream
 }
 
-Storage.prototype.get_package = function(name, callback) {
+Storage.prototype.get_package = function(name, options, callback) {
+	if (typeof(options) === 'function') callback = options, options = {}
+
 	var self = this
 	  , file = name + '/' + info_file
 
diff --git a/lib/storage.js b/lib/storage.js
index 0af05ceba..604f55633 100644
--- a/lib/storage.js
+++ b/lib/storage.js
@@ -385,13 +385,15 @@ Storage.prototype.get_tarball = function(name, filename) {
 //
 // Used storages: local && uplink (proxy_access)
 //
-Storage.prototype.get_package = function(name, callback) {
+Storage.prototype.get_package = function(name, options, callback) {
+	if (typeof(options) === 'function') callback = options, options = {}
+
 	// NOTE: callback(err, result, _uplink_errors)
 	// _uplink_errors is an array of errors used internally
 	// XXX: move it to another function maybe?
 	var self = this
 
-	self.local.get_package(name, function(err, data) {
+	self.local.get_package(name, options, function(err, data) {
 		if (err && (!err.status || err.status >= 500)) {
 			// report internal errors right away
 			return cb(err)
@@ -414,11 +416,11 @@ Storage.prototype.get_package = function(name, callback) {
 		var latest = result['dist-tags'].latest
 
 		async.map(uplinks, function(up, cb) {
-			var oldetag = null
+			var _options = Object.create(options)
 			if (utils.is_object(result._uplinks[up.upname]))
-				oldetag = result._uplinks[up.upname].etag
+				_options.etag = result._uplinks[up.upname].etag
 
-			up.get_package(name, oldetag, function(err, up_res, etag) {
+			up.get_package(name, _options, function(err, up_res, etag) {
 				if (err || !up_res) return cb(null, [err || new Error('no data')])
 
 				try {
diff --git a/lib/up-storage.js b/lib/up-storage.js
index 33c158895..150cae5ed 100644
--- a/lib/up-storage.js
+++ b/lib/up-storage.js
@@ -181,7 +181,9 @@ Storage.prototype.can_fetch_url = function(url) {
 	    && url.path.indexOf(this.url.path) === 0
 }
 
-Storage.prototype.add_package = function(name, metadata, callback) {
+Storage.prototype.add_package = function(name, metadata, options, callback) {
+	if (typeof(options) === 'function') callback = options, options = {}
+
 	this.request({
 		uri: '/' + escape(name),
 		method: 'PUT',
@@ -195,7 +197,9 @@ Storage.prototype.add_package = function(name, metadata, callback) {
 	})
 }
 
-Storage.prototype.add_version = function(name, version, metadata, tag, callback) {
+Storage.prototype.add_version = function(name, version, metadata, tag, options, callback) {
+	if (typeof(options) === 'function') callback = options, options = {}
+
 	this.request({
 		uri: '/' + escape(name) + '/' + escape(version) + '/-tag/' + escape(tag),
 		method: 'PUT',
@@ -209,7 +213,9 @@ Storage.prototype.add_version = function(name, version, metadata, tag, callback)
 	})
 }
 
-Storage.prototype.add_tarball = function(name, filename) {
+Storage.prototype.add_tarball = function(name, filename, options) {
+	if (!options) options = {}
+
 	var stream = new mystreams.UploadTarballStream()
 	  , self = this
 
@@ -248,12 +254,15 @@ Storage.prototype.add_tarball = function(name, filename) {
 	return stream
 }
 
-Storage.prototype.get_package = function(name, etag, callback) {
-	if (etag) {
-		var headers = {
-			'if-none-match': etag
-		}
+Storage.prototype.get_package = function(name, options, callback) {
+	if (typeof(options) === 'function') callback = options, options = {}
+
+	var headers = {}
+	if (options.etag) {
+		headers['If-None-Match'] = options.etag
 	}
+	this._add_proxy_headers(options.req, headers)
+
 	this.request({
 		uri: '/' + escape(name),
 		json: true,
@@ -273,7 +282,8 @@ Storage.prototype.get_package = function(name, etag, callback) {
 	})
 }
 
-Storage.prototype.get_tarball = function(name, filename) {
+Storage.prototype.get_tarball = function(name, options, filename) {
+	if (!options) options = {}
 	return this.get_url(this.config.url + '/' + name + '/-/' + filename)
 }
 
@@ -309,5 +319,23 @@ Storage.prototype.get_url = function(url) {
 	return stream
 }
 
+Storage.prototype._add_proxy_headers = function(req, headers) {
+	if (req) {
+		headers['X-Forwarded-For'] = (
+			(req && req.headers['x-forwarded-for']) ?
+			req.headers['x-forwarded-for'] + ', ' :
+			''
+		) + req.connection.remoteAddress
+	}
+
+	// always attach Via header to avoid loops, even if we're not proxying
+	headers['Via'] =
+		(req && req.headers['via']) ?
+		req.headers['via'] + ', ' :
+		''
+
+	headers['Via'] += '1.1 ' + this.server_id + ' (Sinopia)'
+}
+
 module.exports = Storage