commit 490b8b33b78e318267088d79e362a44d88cc8228 Author: Serene Han keroserene+git@gmail.com Date: Tue Mar 15 20:13:39 2016 -0700

better checks on receiveOffer (#11) --- proxy/proxypair.coffee | 4 +++- proxy/snowflake.coffee | 35 +++++++++++++++-------------------- proxy/spec/snowflake.spec.coffee | 16 ++++++++++++---- 3 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/proxy/proxypair.coffee b/proxy/proxypair.coffee index 3a3fb01..3ed6c6c 100644 --- a/proxy/proxypair.coffee +++ b/proxy/proxypair.coffee @@ -51,7 +51,9 @@ class ProxyPair @client = channel

receiveWebRTCOffer: (offer) -> - console.assert 'offer' == offer.type + if 'offer' != offer.type + log 'Invalid SDP received -- was not an offer.' + return false try err = @pc.setRemoteDescription offer catch e diff --git a/proxy/snowflake.coffee b/proxy/snowflake.coffee index 7cc01c9..4f38029 100644 --- a/proxy/snowflake.coffee +++ b/proxy/snowflake.coffee @@ -50,12 +50,11 @@ CONFIRMATION_MESSAGE = "You're currently serving a Tor user via Snowflake." # Minimum viable snowflake for now - just 1 client. class Snowflake

- relayAddr: null + relayAddr: null proxyPairs: [] - - rateLimit: null - state: MODE.INIT - retries: 0 + rateLimit: null + state: MODE.INIT + retries: 0

constructor: (@broker, @ui) -> rateLimitBytes = undefined @@ -108,16 +107,8 @@ class Snowflake log 'No more available ProxyPair slots.' countdown(err, DEFAULT_BROKER_POLL_INTERVAL / 1000) return - log 'Polling for ' + pair.id recv = @broker.getClientOffer pair.id - recv.then (desc) => - offer = JSON.parse desc - dbg 'Received:\n\n' + offer.sdp + '\n' - console.log desc - sdp = new RTCSessionDescription offer - # @receiveOffer offer - if pair.receiveWebRTCOffer sdp - @sendAnswer pair if 'offer' == sdp.type + recv.then (desc) => @receiveOffer pair, desc , (err) -> countdown(err, DEFAULT_BROKER_POLL_INTERVAL / 1000) @retries++ @@ -129,12 +120,16 @@ class Snowflake return @proxyPairs.find (pp, i, arr) -> return !pp.active

# Receive an SDP offer from some client assigned by the Broker, - # TODO: remove - receiveOffer: (desc) => - sdp = new RTCSessionDescription desc - pair = @nextAvailableProxyPair() - if pair.receiveWebRTCOffer sdp - @sendAnswer pair if 'offer' == sdp.type + # |pair| - an available ProxyPair. + receiveOffer: (pair, desc) => + console.assert !pair.active + try + offer = JSON.parse desc + dbg 'Received:\n\n' + offer.sdp + '\n' + sdp = new RTCSessionDescription offer + @sendAnswer pair if pair.receiveWebRTCOffer sdp + catch e + log 'ERROR: Unable to receive Offer: ' + e

sendAnswer: (pair) -> next = (sdp) -> diff --git a/proxy/spec/snowflake.spec.coffee b/proxy/spec/snowflake.spec.coffee index ca7661b..417b6e6 100644 --- a/proxy/spec/snowflake.spec.coffee +++ b/proxy/spec/snowflake.spec.coffee @@ -47,14 +47,22 @@ describe 'Snowflake', -> expect(s.retries).toBe 1 expect(s.broker.getClientOffer).toHaveBeenCalled()

- it 'receives SDP offer', -> + it 'receives SDP offer and sends answer', -> s = new Snowflake(new FakeBroker(), fakeUI) - s.proxyPairs[0] = { receiveWebRTCOffer: -> } - spyOn(s.proxyPairs[0], 'receiveWebRTCOffer').and.returnValue true + pair = { receiveWebRTCOffer: -> } + spyOn(pair, 'receiveWebRTCOffer').and.returnValue true spyOn(s, 'sendAnswer') - s.receiveOffer { 'type': 'offer', 'sdp': 'foo' } + s.receiveOffer pair, '{"type":"offer","sdp":"foo"}' expect(s.sendAnswer).toHaveBeenCalled()

+ it 'does not send answer when receiving invalid offer', -> + s = new Snowflake(new FakeBroker(), fakeUI) + pair = { receiveWebRTCOffer: -> } + spyOn(pair, 'receiveWebRTCOffer').and.returnValue false + spyOn(s, 'sendAnswer') + s.receiveOffer pair, '{"type":"not a good offer","sdp":"foo"}' + expect(s.sendAnswer).not.toHaveBeenCalled() + it 'can make a proxypair', -> s = new Snowflake(new FakeBroker(), fakeUI) s.makeProxyPair()