Fix connection between two IPv6-only devices with API v1

Python sockets want the IPv6 addresses without embracing brackets, while grpc needs them.
Also, with v1 we didn't actually use IPv6, now we do.

This also incorparates linuxmint#241

Author: Cobinja

src/remote.py

@@ -92,7 +92,7 @@ def start_remote_thread(self):
             func = self.remote_thread_v2
 
         self.remote_thread = threading.Thread(target=func, name="remote-main-thread-v%s-%s-%s:%d-%s"
-                                              % (self.api_version, self.hostname, self.ip_info.ip4_address, self.port, self.ident))
+                                              % (self.api_version, self.hostname, self.ip_info, self.port, self.ident))
         # logging.debug("remote-thread-%s-%s:%d-%s"
                           # % (self.hostname, self.ip_info.ip4_address, self.port, self.ident))
         self.remote_thread.start()
@@ -102,7 +102,7 @@ def remote_thread_v1(self):
 
         self.emit_machine_info_changed() # Let's make sure the button doesn't have junk in it if we fail to connect.
 
-        logging.debug("Remote: Attempting to connect to %s (%s) - api version 1" % (self.display_hostname, self.ip_info.ip4_address))
+        logging.debug("Remote: Attempting to connect to %s (%s) - api version 1" % (self.display_hostname, self.ip_info))
 
         self.set_remote_status(RemoteStatus.INIT_CONNECTING)
 
@@ -113,7 +113,9 @@ def run_secure_loop():
             cert = auth.get_singleton().get_cached_cert(self.hostname, self.ip_info)
             creds = grpc.ssl_channel_credentials(cert)
 
-            with grpc.secure_channel("%s:%d" % (self.ip_info.ip4_address, self.port), creds) as channel:
+            remote_ip, _, ip_version = self.ip_info.get_usable_ip()
+            remote_ip = remote_ip if ip_version == socket.AF_INET else "[%s]" % (remote_ip,)
+            with grpc.secure_channel("%s:%d" % (remote_ip, self.port), creds) as channel:
                 future = grpc.channel_ready_future(channel)
 
                 try:

src/remote_registration.py

@@ -14,6 +14,15 @@
 import prefs
 import config
 
+def get_ipv6_addr_tuple(addr, port):
+    if '%' in addr:
+        ip_part, scope_name = addr.split('%', 1)
+        scope_id = socket.if_nametoindex(scope_name)
+    else:
+        ip_part = addr
+        scope_id = 0
+    return (ip_part, port, 0, scope_id)
+
 class RegRequest():
     def __init__(self, ident, hostname, ip_info, port, auth_port, api_version):
         self.api_version = api_version
@@ -142,20 +151,18 @@ def request(self):
         remote_ip, _, ip_version = self.ip_info.get_usable_ip()
 
         try:
-            ip = remote_ip if ip_version == socket.AF_INET else "[%s]" % (remote_ip,)
             server_sock = socket.socket(ip_version, socket.SOCK_DGRAM)
             server_sock.settimeout(5.0)
-            server_sock.sendto(REQUEST, (ip, self.port))
+            server_sock.sendto(REQUEST, (remote_ip, self.port))
 
             reply, addr = server_sock.recvfrom(2000)
-
-            if addr == (remote_ip, self.port):
+            if (addr[0], addr[1]) == (remote_ip, self.port):
                 return reply
         except socket.timeout:
             logging.debug("Auth: Cert request failed from remote (%s:%d) - (Is their udp port blocked?"
                               % (self.ip_info, self.port))
         except socket.error as e:
-            logging.critical("Something wrong with cert request (%s:%s): " % (remote_ip, self.port, e))
+            logging.critical("Something wrong with cert request (%s:%s): %s" % (remote_ip, self.port, e))
 
         return None
 
@@ -182,7 +189,10 @@ def serve_cert_thread(self, ip_version):
             try:
                 server_sock = socket.socket(ip_version, socket.SOCK_DGRAM)
                 server_sock.settimeout(1.0)
-                server_sock.bind((local_ip, self.port))
+                if ip_version == socket.AF_INET6:
+                    server_sock.bind(get_ipv6_addr_tuple(local_ip, self.port))
+                else:
+                    server_sock.bind((local_ip, self.port))
             except socket.error as e:
                 logging.critical("Could not create udp socket for cert requests: %s" % str(e))
                 return

src/util.py

@@ -243,7 +243,9 @@ def as_binary_list(self):
                 pass
         if self.ip6:
             try:
-                blist.append(socket.inet_pton(GLib.SYSDEF_AF_INET6, self.ip6_address))
+                # Strip scope ID suffix if present (e.g., %eth0)
+                ip6_clean = self.ip6_address.split('%')[0] if '%' in self.ip6_address else self.ip6_address
+                blist.append(socket.inet_pton(GLib.SYSDEF_AF_INET6, ip6_clean))
             except:
                 pass