Move the ability to use Tor vs Meek into the CensorshipCircumvention class so that we can use those endpoints over Tor elsewhere later

cli/onionshare_cli/censorship.py

@@ -25,21 +25,46 @@ from .meek import MeekNotRunning
 class CensorshipCircumvention(object):
     """
     Connect to the Tor Moat APIs to retrieve censorship
-    circumvention recommendations, over the Meek client.
+    circumvention recommendations or the latest bridges.
+
+    We support reaching this API over Tor, or Meek
+    (domain fronting) if Tor is not connected.
     """
 
-    def __init__(self, common, meek, domain_fronting=True):
+    def __init__(self, common, meek=None, onion=None):
         """
         Set up the CensorshipCircumvention object to hold
         common and meek objects.
         """
         self.common = common
-        self.meek = meek
         self.common.log("CensorshipCircumvention", "__init__")
-
+        self.api_proxies = {}
-        # Bail out if we requested domain fronting but we can't use meek
+        if meek:
-        if domain_fronting and not self.meek.meek_proxies:
+            self.meek = meek
-            raise MeekNotRunning()
+            if not self.meek.meek_proxies:
+                raise MeekNotRunning()
+            else:
+                self.common.log(
+                    "CensorshipCircumvention",
+                    "__init__",
+                    "Using Meek with CensorShipCircumvention API",
+                )
+                self.api_proxies = self.meek.meek_proxies
+        if onion:
+            self.onion = onion
+            if not self.onion.is_authenticated:
+                return False
+            else:
+                self.common.log(
+                    "CensorshipCircumvention",
+                    "__init__",
+                    "Using Tor with CensorShipCircumvention API",
+                )
+                (socks_address, socks_port) = self.onion.get_tor_socks_port()
+                self.api_proxies = {
+                    "http": f"socks5h://{socks_address}:{socks_port}",
+                    "https": f"socks5h://{socks_address}:{socks_port}",
+                }
 
     def request_map(self, country=False):
         """
@@ -52,6 +77,8 @@ class CensorshipCircumvention(object):
         Note that this API endpoint doesn't return actual bridges,
         it just returns the recommended bridge type countries.
         """
+        if not self.api_proxies:
+            return False
         endpoint = "https://bridges.torproject.org/moat/circumvention/map"
         data = {}
         if country:
@@ -61,7 +88,7 @@ class CensorshipCircumvention(object):
             endpoint,
             json=data,
             headers={"Content-Type": "application/vnd.api+json"},
-            proxies=self.meek.meek_proxies,
+            proxies=self.api_proxies,
         )
         if r.status_code != 200:
             self.common.log(
@@ -95,6 +122,8 @@ class CensorshipCircumvention(object):
         Optionally, a list of transports can be specified in order to
         return recommended settings for just that transport type.
         """
+        if not self.api_proxies:
+            return False
         endpoint = "https://bridges.torproject.org/moat/circumvention/settings"
         data = {}
         if country:
@@ -105,7 +134,7 @@ class CensorshipCircumvention(object):
             endpoint,
             json=data,
             headers={"Content-Type": "application/vnd.api+json"},
-            proxies=self.meek.meek_proxies,
+            proxies=self.api_proxies,
         )
         if r.status_code != 200:
             self.common.log(
@@ -142,11 +171,13 @@ class CensorshipCircumvention(object):
         """
         Retrieves the list of built-in bridges from the Tor Project.
         """
+        if not self.api_proxies:
+            return False
         endpoint = "https://bridges.torproject.org/moat/circumvention/builtin"
         r = requests.post(
             endpoint,
             headers={"Content-Type": "application/vnd.api+json"},
-            proxies=self.meek.meek_proxies,
+            proxies=self.api_proxies,
         )
         if r.status_code != 200:
             self.common.log(

cli/onionshare_cli/onion.py

@@ -914,7 +914,8 @@ class Onion(object):
         Use the CensorshipCircumvention API to fetch the latest built-in bridges
         and update them in settings.
         """
-        got_builtin_bridges = False
+        builtin_bridges = False
+        meek = None
         # Try obtaining bridges over Tor, if we're connected to it.
         if self.is_authenticated:
             self.common.log(
@@ -922,43 +923,14 @@ class Onion(object):
                 "update_builtin_bridges",
                 "Updating the built-in bridges. Trying over Tor first",
             )
-            (socks_address, socks_port) = self.get_tor_socks_port()
+            self.censorship_circumvention = CensorshipCircumvention(
-            tor_proxies = {
+                self.common, None, self
-                "http": f"socks5h://{socks_address}:{socks_port}",
-                "https": f"socks5h://{socks_address}:{socks_port}",
-            }
-            # Request a bridge
-            r = requests.post(
-                "https://bridges.torproject.org/moat/circumvention/builtin",
-                headers={"Content-Type": "application/vnd.api+json"},
-                proxies=tor_proxies,
             )
-            if r.status_code != 200:
+            builtin_bridges = self.censorship_circumvention.request_builtin_bridges()
-                self.common.log(
-                    "Onion",
-                    "update_builtin_bridges",
-                    f"Trying over Tor failed: status_code={r.status_code}",
-                )
 
-            try:
+        if not builtin_bridges:
-                builtin_bridges = r.json()
+            # Tor was not running or it failed to hit the Tor API.
-                if "errors" in builtin_bridges:
+            # Fall back to using Meek (domain-fronting).
-                    self.common.log(
-                        "Onion",
-                        "update_builtin_bridges",
-                        f"Trying over Tor failed: errors={builtin_bridges['errors']}",
-                    )
-                else:
-                    got_builtin_bridges = builtin_bridges
-            except Exception as e:
-                self.common.log(
-                    "Onion",
-                    "update_builtin_bridges",
-                    f"Hit exception when trying over Tor: {e}",
-                )
-
-        if not got_builtin_bridges:
-            # Fall back to using Meek, without Tor
             self.common.log(
                 "Onion",
                 "update_builtin_bridges",
@@ -966,35 +938,35 @@ class Onion(object):
             )
             meek = Meek(self.common)
             meek.start()
-            self.censorship_circumvention = CensorshipCircumvention(self.common, meek)
+            self.censorship_circumvention = CensorshipCircumvention(
-            got_builtin_bridges = (
+                self.common, meek, None
-                self.censorship_circumvention.request_builtin_bridges()
             )
+            builtin_bridges = self.censorship_circumvention.request_builtin_bridges()
             meek.cleanup()
 
-        # If we got to this point, we have bridges
+        if builtin_bridges:
-        if got_builtin_bridges:
+            # If we got to this point, we have bridges
             self.common.log(
                 "Onion",
                 "update_builtin_bridges",
-                f"Obtained bridges: {got_builtin_bridges}",
+                f"Obtained bridges: {builtin_bridges}",
             )
-            if got_builtin_bridges["meek"]:
+            if builtin_bridges["meek"]:
                 # Meek bridge needs to be defined as "meek_lite", not "meek",
                 # for it to work with obfs4proxy.
                 # We also refer to this bridge type as 'meek-azure' in our settings.
                 # So first, rename the key in the dict
-                got_builtin_bridges["meek-azure"] = got_builtin_bridges.pop("meek")
+                builtin_bridges["meek-azure"] = builtin_bridges.pop("meek")
                 new_meek_bridges = []
                 # Now replace the values. They also need the url/front params appended
-                for item in got_builtin_bridges["meek-azure"]:
+                for item in builtin_bridges["meek-azure"]:
                     newline = item.replace("meek", "meek_lite")
                     new_meek_bridges.append(
                         f"{newline} url=https://meek.azureedge.net/ front=ajax.aspnetcdn.com"
                     )
-                got_builtin_bridges["meek-azure"] = new_meek_bridges
+                builtin_bridges["meek-azure"] = new_meek_bridges
             # Save the new settings
-            self.settings.set("bridges_builtin", got_builtin_bridges)
+            self.settings.set("bridges_builtin", builtin_bridges)
             self.settings.save()
         else:
             self.common.log(