disable for TBB user agents. closes #37

proxy/snowflake.coffee

@@ -48,7 +48,7 @@ MODE =
   WEBRTC_CONNECTING: 1
   WEBRTC_READY:      2
 
-CONFIRMATION_MESSAGE = "You're currently serving a Tor user via Snowflake."
+CONFIRMATION_MESSAGE = 'You\'re currently serving a Tor user via Snowflake.'
 
 # Minimum viable snowflake for now - just 1 client.
 class Snowflake
@@ -222,8 +222,13 @@ snowflakeIsDisabled = ->
   if cookies[COOKIE_NAME] != '1'
     log 'Not opted-in. Please click the badge to change options.'
     return true
+  # Also do nothing if running in Tor Browser.
+  if mightBeTBB()
+    log 'Will not run within Tor Browser.'
+    return true
   return false
 
+
 ###
 Entry point.
 ###

proxy/util.coffee

@@ -5,6 +5,20 @@ Contains helpers for parsing query strings and other utilities.
 ###
 
 
+# It would not be effective for Tor Browser users to run the proxy.
+# Do we seem to be running in Tor Browser? Check the user-agent string and for
+# no listing of supported MIME types.
+TBB_UAS = [
+    'Mozilla/5.0 (Windows NT 6.1; rv:10.0) Gecko/20100101 Firefox/10.0'
+    'Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20100101 Firefox/17.0'
+    'Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Firefox/24.0'
+    'Mozilla/5.0 (Windows NT 6.1; rv:31.0) Gecko/20100101 Firefox/31.0'
+]
+mightBeTBB = ->
+  return TBB_UAS.indexOf(window.navigator.userAgent) > -1 and
+          (window.navigator.mimeTypes and
+           window.navigator.mimeTypes.length == 0)
+
 genSnowflakeID = ->
   Math.random().toString(36).substring(2)